1.L{t² + 1} = 2/s³ + 1/s 2.L{sint + cost} = 1/(s² + 1) + s/(s² + 1) 3.L{et - e^-t} = 1/(s - 1) - 1/(s + 1) 4.L{t³sin²t} = (6/s⁴) * (1 - s/(s² + 4))/2 5.L{t²e^-2t + e^-1cos(2t) + 3} = 2/ (s + 2)³ + 1/(s + 1) * s/(s² + 4) + 3/s
To determine the Laplace transforms of the given functions, we can use the standard Laplace transform formulas. The Laplace transform of a function f(t) is denoted as F(s).
Laplace transform of t² + 1:
The Laplace transform of t² is given by:
L{t²} = 2!/s³ = 2/s³
The Laplace transform of 1 (constant term) is:
L{1} = 1/s
Laplace transform of sint + cost:
The Laplace transform of sint is given by:
L{sint} = 1/(s² + 1)
The Laplace transform of cost is given by:
L{cost} = s/(s² + 1)
Laplace transform of et - e^-t:
The Laplace transform of et is given by:
L{et} = 1/(s - 1)
The Laplace transform of e^-t is given by:
L{e^-t} = 1/(s + 1)
Therefore, the Laplace transform of et - e^-t is:
L{et - e^-t} = 1/(s - 1) - 1/(s + 1)
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Assume that when human resource managers are randomly selected, 57% say job applicants should follow up within two weeks. If 9 human resource managers are randomly selected find the probability that exactly 6 of them say job applicants should follow up within two weeks. The probability is (Round to four decimal places as needed.) if we sample from a small linite population without replacement, the binomial distribution should not be used because the events are not independent. If sampling is done without replacement and the outcomes belong to one of two types, we can use the hypergeometric distribution. If a population has A objects of one type, while the remaining B objects are of the other type, and if n objects are sampled without replacement, then the probability of getting x objects of type A and n-objects of type B under the hypergeometric distribution is given by the following formula. In a lottery game, a bettor selects four numbers from 1 to 47 (without repetition), and a winning tour number combination is later randomly selected. Find the probabilities of getting exactly two winning numbers with one ticket (Hint: Use A = 4,8 43, 4, and X2) Al В (A+B) POX) (A XX! (8-tin-xl (AB-nin! P=2 (Round to four decimal places as needed.) If we sample from a small finite population without replacement, the binomial distribution should not be used because the events are not independent. If sampling is done without replacement and the outcomes belong to one of two types, we can use the hypergeometric distribution, if a population has a objects of one type, while the remaining B objects are of the other type, and if n objects are sampled without replacement, then the probability of getting x objects of type A and n-x objects of type B under the hypergeometric distribution is given by the following formula In a lottery game, a bettor selects four numbers from 1 to 47 (without repetition), and a winning four-number combination is teter randomly selected. Find the probabilities of getting exactly two winning numbers with one ticket. (Hint USA 4, B=43, n = 4, and x=23 AI B! (A+BY PX) (A-XIX (B x - x)(A+B nint P(2)= {Round to four decimal places as needed.)
In the first scenario, where 9 human resource managers are randomly selected and we want to find the probability that exactly 6 of them say job applicants should follow up within two weeks, we can use the hypergeometric distribution since the sampling is done without replacement and the outcomes belong to two types. The probability is (Round to four decimal places as needed.)
First scenario: For the probability of exactly 6 out of 9 human resource managers saying applicants should follow up within two weeks, we use the hypergeometric distribution. Given A = 9 * 0.57 = 5.13 (rounded to the nearest whole number), B = 9 - A = 3.87 (rounded to the nearest whole number), n = 9, and x = 6, we can calculate the probability using the formula:
P(6) = (5 choose 6) * (3 choose 9-6) / (5+3 choose 9)
Second scenario: To find the probability of getting exactly 2 winning numbers with one ticket in the lottery game, we can again use the hypergeometric distribution. Here, A = 4 (number of winning numbers), B = 47 - A = 43 (remaining numbers), n = 4 (numbers chosen), and x = 2 (winning numbers selected). Using the formula:
P(2) = (4 choose 2) * (43 choose 4-2) / (4+43 choose 4)
By substituting the values into the formulas and performing the calculations, we can find the probabilities in both scenarios, rounding to four decimal places as needed.
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A corporation has four shareholders. The 10,000 shares in this corporation are divided among the shareholders as follows: Shareholder A owns 2650 shares (26.5% of the company) Shareholder B owns 2550 shares (25.5% of the company) Shareholder C owns 2500 shares (25% of the company). Shareholder D owns 2300 shares (23% of the company) Assume that decisions are made by strict majority vote. Does the individual with 23% hold any effective power in voting?
No, the individual with 23% of the shares does not hold any effective power in voting. In a strict majority vote, decisions are made based on a simple majority, meaning that more than 50% of the total votes are required to pass a resolution.
In this case, the total number of shares is 10,000. Shareholder A, B, C, and D collectively own [tex]2650 + 2550 + 2500 + 2300 = 10,000[/tex] shares, which is the entire company.
Since Shareholder D owns only 23% of the shares (2300 shares out of 10,000), it is not enough to reach the majority threshold. Shareholders A, B, and C collectively own 76.5% of the shares [tex](2650 + 2550 + 2500 = 7700[/tex] shares), which is more than enough to achieve a strict majority.
Therefore, Shareholder D with 23% of the shares does not hold any effective power in voting because they cannot single-handedly influence or decide the outcome of any vote due to not having a majority stake in the company.
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Confidence interval example рді Problem: A local farmer's market wants. to know the average (mean) number of puunds of tomato bought by customers. We check that 7 customers bought of 6 pounds with a standard deviation of 2 pounds. Find the mean of the population using a 90% confidence interval. a mean Solution: We need to determine the following interval for M, the mean s X-t ≤M≤X + t where X=Sample mean From problem; x = 6 5 = 2 (n=7) S = Sample Standard deviation. n = sample size te is found from Table 4. level of confidence. dific .90 - C = 0.90 90% 1 (1.943)
The mean of the population using a 90% confidence interval is between 4.33 and 7.67 pounds of tomato.
We need to find the following interval for M, the mean: X-t ≤M≤X + t
where X = sample mean
From the problem, x = 6 S = sample standard deviation, which is 2. n = sample size.t-value is found from
Table 4. We know that the level of confidence is 90% or 0.90. df = n - 1 = 7 - 1 = 6.
Therefore, t-value with a degree of freedom of 6 and a level of significance of 0.10 is equal to 1.943 (from Table 4).
Using the given formula, we can determine the lower and upper limits of the confidence interval:
X - t (S / √n) ≤ M ≤ X + t (S / √n)
6 - 1.943 (2 / √7) ≤ M ≤ 6 + 1.943 (2 / √7)
4.33 ≤ M ≤ 7.67
Therefore, the mean of the population using a 90% confidence interval is between 4.33 and 7.67 pounds of tomato.
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Suppose that a 2 x 2 matrix A has an eigenvalue 2 with corresponding eigenvector and an eigenvalue -2 with corresponding eigenvector [3] Find an invertible matrix P and a diagonal matrix D so that A = PDP-1.
The matrix A is similar to the diagonal matrix D with eigenvalues 2 and -2 and P is the invertible matrix that diagonalizes the matrix A. Let matrix A be a 2 x 2 matrix with eigenvalues 2 and -2 with corresponding eigenvectors x1 = [1,1] and x2 is [-1,1], respectively. Then the matrix A can be diagonalized.
Step-by-step answer:
Given that A is a 2 x 2 matrix with eigenvalues 2 and -2 with corresponding eigenvectors
x1 = [1,1] and
x2 = [-1,1], respectively. Then the matrix A can be diagonalized. A matrix is diagonalizable if it has n linearly independent eigenvectors, where n is the order of the matrix. Since the matrix A has two linearly independent eigenvectors x1 and x2, then it is diagonalizable. Let P be the matrix whose columns are the eigenvectors x1 and x2, respectively.
Then P = [1,-1;1,1].
Let D be the diagonal matrix whose diagonal entries are the corresponding eigenvalues.
Then D = diag (2,-2).
Thus, A = PDP⁻¹
= [1,-1;1,1]·diag (2,-2)·[1,1;-1,1]/2
= [[2,0],[0,-2]].
Therefore, A can be diagonalized and is similar to the diagonal matrix D with eigenvalues 2 and -2 and P is invertible matrix that diagonalizes the matrix A.
In conclusion, we can use the formula A = PDP⁻¹ to find the invertible matrix P and a diagonal matrix D for a 2 x 2 matrix A with eigenvalues 2 and -2 and corresponding eigenvectors [1,1] and [-1,1], respectively. The matrix A is similar to the diagonal matrix D with eigenvalues 2 and -2 and P is the invertible matrix that diagonalizes the matrix A.
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A=9, B=0, C=0, D=0, E=0, F=0 Under the revision of government policies,it is proposed to allow sales of Pocket Calculators on the metro trains during off-peak hours.The vendor can purchase the pocket calculator at a special discounted rate of (c + d) Baisa per calculator against the selling price of (2 * c + 2 * d)Baisa. Any unsold Calculators are, however a dead loss. A vendor has estimated the following probability distribution for the number of calculators demanded. No.of calculators demanded 10 11 12 13 14 15 Probability 0.05 0.14 0.45 0.2 0.1 0.06 How many Calculators should he order so that his expected profit will be maximum? (25 marks)
Calculate the number of calculators for maximum expected profit using the given probability distribution.
To determine the number of calculators the vendor should order for maximum expected profit, we need to calculate the expected profit for each possible quantity of calculators based on the given probability distribution.
The expected profit can be calculated by multiplying the profit for each quantity by its corresponding probability, summing up these values for all quantities. The profit for each quantity can be obtained by subtracting the cost (c + d) from the selling price (2 * c + 2 * d) and multiplying it by the number of calculators demanded.
By evaluating the expected profit for various quantities, the vendor can identify the quantity that yields the maximum expected profit. This quantity would be the optimal order quantity that balances the potential demand and the risk of unsold calculators.
Performing these calculations using the given probability distribution will provide the answer to maximize the expected profit.
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(1 point) Solve for X. X = 11 I 4 -3 [13]×+B2 ³]-[R3² 3]×x. X = X. -9
(1 point) Given the matrix (a) does the inverse of the matrix exist? Your answer is (input Yes or No): (b) if your answer is
The given expression is X = 11 I 4 -3 [13]×+B2 ³]-[R3² 3]×x. X= [11 1/4 -3] [13xB2³] [-R3² 3x]X = X - 9.
Given, X = 11 I 4 -3 [13]×+B2 ³]-[R3² 3]×x. Adding up the values, we get, X = [11 1/4 -3] [13xB2³] [-R3² 3x]x. X = X - 9. Let's consider the matrix [11 1/4 -3] [13xB2³] [-R3² 3x]x.
The determinant of the matrix is given by: (11 x 2 x 3) - (1/4 x 13 x 3) + (-3 x 13 x R3²) = 66 - (13/4) x 3 x R3². As the determinant is not equal to zero, the inverse of the matrix exists.
(a) Yes, the inverse of the matrix exists.
(b) The answer is not applicable.
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The data in the table represent the weights of valus domestic cars and the miles per galan in the city for the 2000 model ya For the data the leasts rege per gelos Computs the coefficient at determination of the expanded date set. What effect does the son of the health car to the data set Save Cick the icon to view the data table The caufficient of determination of the expanded data was R²-| || Round is one decimal place as needed)
Based on the question, it seems like there may be some typos or errors in the wording. However, assuming the question is asking for the coefficient of determination for a set of data on the weights and miles per gallon of 2000 model year domestic cars, we can calculate this using a statistical software program or calculator.
The coefficient of determination (also known as R-squared) is a measure of how well a regression model fits the data, with values ranging from 0 to 1. A higher R-squared value indicates a better fit.
Without the actual data set, I cannot calculate the coefficient of determination for the expanded data set. However, assuming we have the data, we could calculate it using regression analysis.
As for the second part of the question, it is unclear what is meant by "the son of the health car" and how it relates to the data set. Please provide more information or clarify the question if possible.
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Using the transformations u=x-y and v=x+y to evaluate ·JJ x-y/x+y dA over a square region with vertices (0.2): (1.1): (2.2) and (1,3), which ONE of the following values will be the CORRECT VALUE of the double integral?
The correct value of the double integral is 8.
For evaluate the integral ∫∫ x-y/x+y dA over the given square region, we can use the transformations u = x - y and v = x + y.
Then, the region of integration in the (x, y) plane maps to the region of integration in the (u, v) plane as follows:
(0, 2) → (-2, 2)
(1, 1) → (0, 2)
(2, 2) → (0, 4)
(1, 3) → (-2, 4)
The Jacobian of this transformation is given by:
∂(u, v)/∂(x, y) = 2
So, the integral becomes:
∫∫ x-y/x+y dA = ∫∫ (u+v)/2 dudv
Integrating this over the region in the (u, v) plane, we get: ·
∫∫ (u+v)/2 dudv = 1/2 ∫∫ u dudv + 1/2 ∫∫ v dudv
Integrating over the limits of integration, we get:
1/2∫∫ u dudv = 0
1/2 ∫∫ v dudv = (1/2) × [(2) - (-2)] × [(4-0)/2]
= 8
Therefore, the correct value of the double integral is 8.
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If events A and B are independent, then P(AB) is equal to:
A. P(A).P(B|A)
B. P(B)
C. P(A)
D. P(A).P(B)
If events A and B are independent, then P(AB) is equal to D. P(A).P(B).
Independent events are those events whose outcomes do not affect each other.
Therefore, P(AB) = P(A) * P(B), if events A and B are independent.
This means that the probability of both A and B happening equals the probability of A happening times the probability of B happening, given that A has happened.
The formula is expressed as follows:
P(AB) = P(A) * P(B), if A and B are independent.
Where P(A) is the probability of A and P(B) is the probability of B happening.
Let's check other options whether they are correct or not:
A. P(A).P(B|A):
This formula can be used only if A and B are dependent. It is not applicable to independent events.
B. P(B):P(B) is the probability of event B occurring, it doesn't take into account event A, hence it is wrong.
C. P(A):P(A) is the probability of event A occurring, it doesn't take into account event B, hence it is wrong.
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need help with calc 2 .
Show all work please .
Circle the correct answer in each part below and show all the steps to justify your choices. (a) True or False: If limn→[infinity] 5an an+1 = 3, then 1 an converges absolutely.
The statement given is false. The absolute convergence of 1/an cannot be determined solely based on the given information about the limit of 5an/(an+1).
In the given problem, we are given the limit of the sequence 5an/(an+1) as n approaches infinity, which is equal to 3. However, this information alone is not sufficient to determine the absolute convergence of the sequence 1/an.
To determine the absolute convergence of 1/an, we need to consider the behavior of the sequence an itself. The limit of 5an/(an+1) gives us some information about the ratio of consecutive terms, but it does not provide direct information about the convergence of an. The convergence or divergence of an can only be determined by analyzing the behavior of the terms in the sequence an itself.
Therefore, without any additional information about the sequence an, we cannot conclude anything about the absolute convergence of 1/an. The statement given in the problem, that 1/an converges absolutely based on the given limit, is false.
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Solve the following equations.
a) +=(Hint: use the quadratic formula)
b) log₂ (x + 5) - log₂ (x - 1) = log₂ 10 - log₂ 2
c) √x + 27 = 2 + √x-5
d) 3x+1-3x = 162 (Hint: use exponent rules)
e) y x-10 (Hint: First, simplify the system) y+10
2. (10 points): Given the function, f(x)=x57x¹ + 12x³
a) Find the stationary points of f(x).
b) Characterize the stationary points of f(x).
(a) Solve the equation using the quadratic formula. (b) Simplify the logarithmic equation and solve for x. (c) Isolate the square root term and solve for x. (d) Simplify the equation and solve for x using exponent rules. (e) Simplify the system of equations and solve for y and x. (f) Find the stationary points of the given function and characterize them.
(a) To solve the equation x^2 - 2x - 15 = 0, we can use the quadratic formula. Plugging in the coefficients, we have x = (-(-2) ± √((-2)^2 - 4(1)(-15))) / (2(1)). Simplifying this expression will give the solutions for x.
(b) For the equation log₂ (x + 5) - log₂ (x - 1) = log₂ 10 - log₂ 2, we can simplify the equation using logarithmic properties and solve for x.
(c) In the equation √x + 27 = 2 + √x - 5, we can isolate the square root term and solve for x.
(d) Simplifying the equation 3x+1-3x = 162 using exponent rules, we can solve for x.
(e) For the system of equations y^(x-10) = y + 10 and y^2 = 10, we can simplify the system by substituting the second equation into the first equation. Then, we can solve for y and x.
(f) To find the stationary points of the function f(x) = x^5 + 7x - 12x^3, we take the derivative of the function, set it equal to zero, and solve for x. The solutions will give the x-coordinates of the stationary points. To characterize the stationary points, we can analyze the behavior of the derivative around each point and determine whether they are local maximums, local minimums, or points of inflection.
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\Finding percentiles for Z~N(0;1). Question 6: Find the z-value that has an area under the Z-curve of 0.1292 to its left. Question 7: Find the z-value that has an area under the Z-cu
To find the z-value that has an area under the Z-curve of 0.1292 to its left, the z-value that has an area under the Z-curve of 0.8508 to its left is 1.04.
If we know the area to the left of a certain z-value on the standard normal distribution, we can use the standard normal distribution table to determine the z-value corresponding to that area. Using the table, we look for the area closest to 0.1292, which is 0.1292, in the left-hand column.0.1292 lies between 0.12 and 0.13 in the left-hand column of the standard normal distribution table.
In the top row, we look for the number 0.00 since we're dealing with a standard normal distribution. We now follow the row and column that correspond to 0.12 and 0.00, and we find the value 1.10 in the body of the table. Since the area to the left of z is 0.1292, z must be -1.10 to satisfy this requirement. Therefore, the z-value that has an area under the Z-curve of 0.1292 to its left is -1.10.
To find the z-value that has an area under the Z-curve of 0.8508 to its left:If we know the area to the left of a certain z-value on the standard normal distribution, we can use the standard normal distribution table to determine the z-value corresponding to that area.Using the table, we look for the area closest to 0.8508, which is 0.8508, in the left-hand column. 0.8508 lies between 0.84 and 0.85 in the left-hand column of the standard normal distribution table.
In the top row, we look for the number 0.00 since we're dealing with a standard normal distribution. We now follow the row and column that correspond to 0.84 and 0.00, and we find the value 1.04 in the body of the table. Since the area to the left of z is 0.8508, z must be 1.04 to satisfy this requirement. Therefore, the z-value that has an area under the Z-curve of 0.8508 to its left is 1.04.
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QUESTION 6 dy Find dx for In (2x – 3y) = cos(V5y) +43°y? by using implicit differentiation. [7 marks]
Th solution of the differentiation is dx/dy = [-(2x – 3y) * sin(√5y) * d(√5y)/dy + 43° * (2x – 3y)] / -3
To find dx for the given equation using implicit differentiation, we will differentiate both sides of the equation with respect to y. Let's break down the process step by step:
To differentiate the natural logarithm function In(2x – 3y) with respect to y, we need to use the chain rule. The chain rule states that if we have a function of the form f(g(y)), then its derivative with respect to y is given by f'(g(y)) * g'(y). In this case, g(y) is 2x – 3y, and f(g(y)) is In(g(y)).
Using the chain rule, we differentiate In(2x – 3y) with respect to y as follows:
d/dy(In(2x – 3y)) = d/d(2x – 3y)(In(2x – 3y)) * d/dy(2x – 3y)
The derivative of In(2x – 3y) with respect to (2x – 3y) is 1/(2x – 3y) multiplied by the derivative of (2x – 3y) with respect to y, which is -3.
Therefore, we have:
1/(2x – 3y) * (-3) * (d(2x – 3y)/dy) = -3/(2x – 3y) * (d(2x – 3y)/dy)
To differentiate cos(√5y) + 43°y with respect to y, we need to apply the rules of differentiation. The derivative of cos(√5y) is given by -sin(√5y) * d(√5y)/dy, and the derivative of 43°y with respect to y is simply 43°.
Therefore, we have:
d/dy(cos(√5y) + 43°y) = -sin(√5y) * d(√5y)/dy + 43°
Now that we have the derivatives of both sides of the equation, we can equate them:
-3/(2x – 3y) * (d(2x – 3y)/dy) = -sin(√5y) * d(√5y)/dy + 43°
We are interested in finding dx, the derivative of x with respect to y. To isolate dx, we need to rearrange the equation and solve for d(2x – 3y)/dy:
-3/(2x – 3y) * (d(2x – 3y)/dy) = -sin(√5y) * d(√5y)/dy + 43°
Multiply both sides of the equation by (2x – 3y) to get rid of the denominator:
-3 * (d(2x – 3y)/dy) = -(2x – 3y) * sin(√5y) * d(√5y)/dy + 43° * (2x – 3y)
Now, we can solve for d(2x – 3y)/dy:
d(2x – 3y)/dy = [-(2x – 3y) * sin(√5y) * d(√5y)/dy + 43° * (2x – 3y)] / -3
Finally, since we are looking for dx, the derivative of x with respect to y, we can rewrite d(2x – 3y)/dy as dx/dy:
dx/dy = [-(2x – 3y) * sin(√5y) * d(√5y)/dy + 43° * (2x – 3y)] / -3
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Let the random variable X follow a normal distribution with u = 70 and O2 = 64. a. Find the probability that X is greater than 80. b. Find the probability that X is greater than 55 and less than 80. c. Find the probability that X is less than 75. d. The probability is 0.1 that X is greater than what number? e. The probability is 0.05 that X is in the symmetric interval about the mean between which two numbers? Click the icon to view the standard normal table of the cumulative distribution function. a. The probability that X is greater than 80 is 0.1056 (Round to four decimal places as needed.) b. The probability that X is greater than 55 and less than 80 is 0.8640 . (Round to four decimal places as needed.) c. The probability that X is less than 75 is 0.7341 . (Round to four decimal places as needed.) d. The probability is 0.1 that X is greater than (Round to one decimal place as needed.)
To solve these probability problems, we will use the properties of the standard normal distribution. Given that X follows a normal distribution with a mean (μ) of 70 and a variance ([tex]\sigma^2[/tex]) of 64, we can standardize the values using the formula [tex]Z = \frac{{X - \mu}}{{\sigma}}[/tex], where Z is the standard normal random variable.
a) Find the probability that X is greater than 80:
To find this probability, we need to calculate the area under the standard normal curve to the right of Z = (80 - 70) / [tex]\sqrt 64[/tex] is 1.25. Using a standard normal table or calculator, we can find that the probability is approximately 0.1056.
b) Find the probability that X is greater than 55 and less than 80:
First, we calculate Z1 = (55 - 70) / [tex]\sqrt 64[/tex] is -2.1875, which corresponds to the left endpoint. Then we calculate Z2 = (80 - 70) / [tex]\sqrt 64[/tex] is 1.25, which corresponds to the right endpoint. The probability is the area under the standard normal curve between Z1 and Z2. By looking up the values in the standard normal table or using a calculator, we find that the probability is approximately 0.8640.
c) Find the probability that X is less than 75:
We calculate Z = (75 - 70) / [tex]\sqrt 64[/tex] is 0.78125. The probability is the area under the standard normal curve to the left of Z. By looking up the value in the standard normal table or using a calculator, we find that the probability is approximately 0.7341.
d) Find the probability that X is greater than a certain number:
To find the value of X for a given probability, we need to find the corresponding Z value. In this case, the probability is 0.1, which corresponds to a Z value of approximately 1.28. We can solve for X using the formula [tex]Z = \frac{{X - \mu}}{{\sigma}}[/tex]. Rearranging the formula, we have X = Z * σ + μ. Substituting the values, we get X = 1.28 * [tex]\sqrt 64[/tex] + 70 ≈ 79.92. So, the probability is 0.1 that X is greater than approximately 79.9.
e) Find the symmetric interval about the mean for a given probability:
The symmetric interval is the range of values around the mean that contains a given probability. In this case, the probability is 0.05, which corresponds to each tail of the distribution. To find the Z value for each tail, we divide the total probability by 2. So, each tail has a probability of 0.025. By looking up this value in the standard normal table or using a calculator, we find that the Z value is approximately 1.96. Now we can solve for the values of X using the formula X = Z * σ + μ. The lower value is -1.96 * [tex]\sqrt 64[/tex] + 70 ≈ 56.32, and the upper value is 1.96 * [tex]\sqrt 64[/tex] + 70 ≈ 83.68. Therefore, the symmetric interval about the mean between the two numbers is approximately [56.32, 83.68].
The correct answers are:
a) The probability that X is greater than 80 is 0.1056 (rounded to four decimal places).
b) The probability that X is greater than 55 and less than 80 is 0.8640 (rounded to four decimal places).
c) The probability that X is less than 75 is 0.7341 (rounded to four decimal places).
d) The probability is 0.1 that X is greater than approximately 79.9 (rounded to one decimal place).
e) The probability is 0.05 that X is in the symmetric interval about the mean between approximately 56.32 and 83.68.
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The region |z+i|<1 has no interior points. Select one: O True O False The region |z - i| > 1 hasi as an interior point. Select one: a True b.False
The statement "The region |z+i|<1 has no interior points" is False. The region |z + i| < 1 does have interior points.
To determine the interior points of the region |z + i| < 1, we need to consider the inequality and understand what it represents geometrically. The inequality |z + i| < 1 describes all complex numbers z that are located within a circle in the complex plane centered at -i with a radius of 1.
To find the interior points, we need to identify the points within the circle that satisfy the inequality. In this case, all points within the circle satisfy the inequality because the inequality is strict (<) rather than inclusive (≤). Therefore, every point inside the circle is considered an interior point.
To summarize, the region |z + i| < 1 has interior points since all points within the circle defined by the inequality satisfy the condition. Therefore, the statement "The region |z + i| < 1 has no interior points" is False.
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find the indicated partial derivative. r(s, t) = tes/t; rt(0, 5)
The partial derivative rt(0, 5) of the function r(s, t) = tes/t is -e/5.
To find the indicated partial derivative, we need to differentiate the function r(s, t) with respect to the variable t while keeping s constant.
Given: r(s, t) = tes/t
To find rt(0, 5), we differentiate r(s, t) with respect to t and then substitute s = 0 and t = 5 into the resulting expression.
Taking the partial derivative of r(s, t) with respect to t, we use the quotient rule:
∂r/∂t = (∂/∂t)(tes/t)
= (t * ∂/∂t)(es/t) - (es/t * ∂/∂t)(t)
= (t * (e/t) * ∂/∂t)(s) - (es/t * 1)
= (e/t * s) - (es/t)
= es/t * (s - 1)
Now we substitute s = 0 and t = 5 into the expression we obtained:
rt(0, 5) = e(5)/5 * (0 - 1)
= e/5 * (-1)
= -e/5
Therefore, rt(0, 5) is equal to -e/5.
In conclusion, the partial derivative rt(0, 5) of the function r(s, t) = tes/t is -e/5.
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A group of thieves are planning to burglarize either Warehouse A or Warehouse B. The owner of the warehouses has the manpower to secure only one of them. If Warehouse A is burglarized the owner will lose $20,000, and if Warehouse B is burglarized the owner will lose $30,000. There is a 40% chance that the thieves will burglarize Warehouse A and 60% chance they will burglarize Warehouse B. There is a 30% chance that the owner will secure Warehouse A and 70% chance he will secure Warehouse B. What is the owner's expected loss?
The owner's expected loss is $26,000
To calculate the owner's expected loss, we need to consider the probabilities of each event and the corresponding losses associated with each event.
Let's define the random variables as follows:
A: Event of Warehouse A being burglarized
B: Event of Warehouse B being burglarized
The losses are:
Loss(A) = $20,000 (if Warehouse A is burglarized)
Loss(B) = $30,000 (if Warehouse B is burglarized)
The probabilities are:
P(A) = 0.40 (chance of Warehouse A being burglarized)
P(B) = 0.60 (chance of Warehouse B being burglarized)
P(A') = 0.30 (chance of Warehouse A being secured)
P(B') = 0.70 (chance of Warehouse B being secured)
The expected loss can be calculated using the following formula:
Expected Loss = P(A) * Loss(A) + P(B) * Loss(B)
Substituting the values, we have:
Expected Loss = (0.40 * $20,000) + (0.60 * $30,000)
Expected Loss = $8,000 + $18,000
Expected Loss = $26,000
This means that, on average, the owner can expect to lose $26,000 due to burglaries in either Warehouse A or Warehouse B, considering the probabilities and corresponding losses involved.
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Consider the standard one-period binomial option pricing model. Denote the one-period risk-free rate by r and the current price of a non-dividend paying stock S. Assume that in one period the stock price will either have risen to uS or fallen to dS where d< 1<1+r
we can find the option price at time t=0 by discounting the expected option price at time t=1: V₀ = (1 / (1 + r)) * (p * V_u + (1 - p) * V_d)
In the one-period binomial option pricing model, we consider a stock price that can either rise to uS or fall to dS, where d < 1 < 1 + r. Here, u represents the upward movement factor, d represents the downward movement factor, and S is the current price of the non-dividend paying stock.
Let's denote the option price at time t=0 as V₀, and the option price at time t=1 as V₁.
At time t=1, there are two possible scenarios: the stock price either rises to uS or falls to dS. We assume that the risk-free rate is r.
To find the option price at time t=0, we use a risk-neutral probability approach. Let p be the probability of an upward movement and (1-p) be the probability of a downward movement.
The expected option price at time t=1, discounted at the risk-free rate, is given by:
V₁ = p * V_u + (1 - p) * V_d
where V_u represents the option price at time t=1 if the stock price rises to uS, and V_d represents the option price at time t=1 if the stock price falls to dS.
Since the option price at time t=1 is determined by the payoffs in the two scenarios, we have:
V_u = max(uS - K, 0) (option payoff if the stock price rises to uS)
V_d = max(dS - K, 0) (option payoff if the stock price falls to dS)
Here, K represents the strike price of the option.
To find the risk-neutral probability p, we use the following equation:
p = (1 + r - d) / (u - d)
Finally, we can find the option price at time t=0 by discounting the expected option price at time t=1:
V₀ = (1 / (1 + r)) * (p * V_u + (1 - p) * V_d)
This equation gives us the option price at time t=0 in the one-period binomial option pricing model.
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ed Consider the following linear transformation of IR³: T(x1, x2, 3)=(-4-₁-4 x2 + x3, 4-1+4.2- I3, . (A) Which of the following is a basis for the kernel of T? O(No answer given) O {(4, 0, 16), (-1, 1, 0), (0, 1, 1)} O {(-1,0,-4), (-1,1,0)} O {(0,0,0)} O {(-1,1,-5)} [6marks] (B) Which of the following is a basis for the image of T? (B) Which of the following is a basis for the image of T? O(No answer given) O {(1, 0, 4), (-1, 1, 0), (0, 1, 1)} O {(-1,1,5)} O {(1, 0, 0), (0, 1, 0), (0, 0, 1)} O {(2,0, 8), (1,-1,0)}
In the given linear transformation T(x1, x2, x3) = (-4x1 - 4x2 + x3, 4x1 + 4x2 - x3, 0), we need to determine the basis for the kernel and the image of T.
The basis for the kernel is {(0, 0, 0)}, and the basis for the image is {(1, 0, 0), (0, 1, 0), (0, 0, 1)}.
(A) To find the basis for the kernel of T, we need to determine the set of vectors that get mapped to the zero vector (0, 0, 0) under the transformation T.
By solving the system of equations -4x1 - 4x2 + x3 = 0, 4x1 + 4x2 - x3 = 0, and 0 = 0, we find that the only solution is x1 = x2 = x3 = 0. Therefore, the kernel of T is { (0, 0, 0) }.
(B) To find the basis for the image of T, we need to determine the set of vectors that can be obtained as the result of the transformation T.
From the transformation T, we can observe that the image of T spans the entire three-dimensional space IR³, since all possible combinations of x1, x2, and x3 can be obtained as outputs. Therefore, a basis for the image of T is {(1, 0, 0), (0, 1, 0), (0, 0, 1)}.
In summary, the basis for the kernel of T is {(0, 0, 0)}, and the basis for the image of T is {(1, 0, 0), (0, 1, 0), (0, 0, 1)}.
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The line p po+tu intersects a sphere centered on the origin with radius 10 at two points, where p. (-2.2. 1) and (1.-2. 2) The value of t for one of those intersection points is t 1 Determine the value of t for the other intersection point. Express your answer in the form t-1/x where x is an integer, and enter the value of x below. The correct answer is an integer. Enter it without any decimal point
Given a line defined by p = po + tu that intersects a sphere centered at the origin with radius 10 at two points, where p = (-2, 2, 1) and (1, -2, 2), we are asked to find the value of t for the other intersection point. We will determine this value by solving for t using the equation of the sphere and the given points.
The equation of a sphere centered at the origin with radius 10 is [tex]x^2 + y^2 + z^2 = 10^2[/tex].
Using the point (-2, 2, 1), we can substitute these coordinates into the equation of the sphere:
[tex](-2)^2 + 2^2 + 1^2 = 10^2[/tex]
4 + 4 + 1 = 100
9 = 100
Since the left side does not equal the right side, this point does not lie on the sphere, indicating that it is not one of the intersection points.
Now, let's consider the point (1, -2, 2). Substituting these coordinates into the equation of the sphere:
[tex]1^2 + (-2)^2 + 2^2 = 10^2[/tex]
1 + 4 + 4 = 100
9 = 100
Again, the left side does not equal the right side, indicating that this point is not on the sphere either.
Since neither of the given points lie on the sphere, it is likely that there was an error or misunderstanding in the question. As a result, we are unable to determine the value of t for the other intersection point.
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please see attached question
answer parts E,F and G
will like and rate if correct
please show all workings and correct answer will rate if
so.
Determine whether each of the following sequences with given nth term converges or diverges. find the limit of those sequences that converge :
(e) an = 2n+2 +5 3n-1 (f) an = (n + 4) 1/2 (g) an = (-1)
(e) To determine whether the sequence given by the nth term an = (2n+2) / (3n-1) converges or diverges, we can analyze its behavior as n approaches infinity.
Taking the limit of an as n approaches infinity:
lim(n→∞) (2n+2) / (3n-1)
We can simplify this expression by dividing both the numerator and denominator by n:
lim(n→∞) (2 + 2/n) / (3 - 1/n)
As n approaches infinity, the terms 2/n and 1/n become smaller and tend to zero:
lim(n→∞) (2 + 0) / (3 - 0)
Simplifying further, we get:
lim(n→∞) 2/3 = 2/3
Therefore, the sequence converges to the limit 2/3.
(f) For the sequence given by the nth term an = (n + 4)^(1/2), we need to determine its convergence or divergence.
Taking the limit of an as n approaches infinity:
lim(n→∞) (n + 4)^(1/2)
As n approaches infinity, the term n dominates the expression. Thus, we can disregard the constant 4 in comparison.
Taking the square root of n as n approaches infinity:
lim(n→∞) (√n)
The square root of n also approaches infinity as n increases.
Therefore, the sequence diverges to positive infinity as n approaches infinity.
(g) For the sequence given by the nth term an = (-1)^n, we can analyze its convergence or divergence.
The sequence alternates between -1 and 1 as n increases. It does not approach a specific value or tend to infinity.
Therefore, the sequence diverges since it does not have a finite limit.
To summarize:
(e) The sequence converges to the limit 2/3.
(f) The sequence diverges to positive infinity.
(g) The sequence diverges.
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Determine the slope-intercept equation for the line through (1,1) which is perpendicular to the other line z+y = 4
Therefore, the slope-intercept equation for the line through (1,1) that is perpendicular to the other line z+y=4 is y=x+0.
We need to determine the slope-intercept equation for the line through (1,1) which is perpendicular to the other line z+y=4..
The slope-intercept form is y=mx+b, where m is the slope and b is the y-intercept, which is where the line intersects the y-axis.
If we want to write a line in slope-intercept form, we must have its slope and y-intercept.
We can determine the slope of a line by rearranging it into y=mx+b form.
y=mx+b is the slope-intercept form of a line where m represents the slope.
Let's rearrange the given equation in the slope-intercept form as follows:
y=-z+4
Let us determine the slope of the line. From the equation, the coefficient of z is -1, which represents the slope of the line.
Therefore, the slope of the line is -1.
The slope of a line perpendicular to a given line is the negative reciprocal of that line's slope.
Therefore, the slope of a line perpendicular to the given line is 1.
Let us apply point-slope form to find the equation of the line. We know that the line passes through the point (1, 1) and has a slope of 1.
y-y1=m(x-x1) y-1=1(x-1) y-1=x-1 y=x
Therefore, the equation of the line that passes through (1,1) with a slope of 1 is y=x.
We can write this equation in slope-intercept form by rearranging it as:
y=x+0
Therefore, the slope-intercept equation for the line through (1,1) that is perpendicular to the other line z+y=4 is y=x+0.
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Suppose we are doing a hypothesis test and we can reject H0 at
the 5% level of significance, can we reject the same H0 (with the
same H1) at the 10% level of significance?
This question concerns some
If we can reject H₀ at the 5% level of significance, then we can also reject the same H₀ with the same H₁ at the 10% level of significance.
If we can reject the null hypothesis H₀ at the 5% level of significance, then it implies that the probability of getting a sample mean, as extreme as the one we have observed, under the null hypothesis is less than 5%. Hence, we can reject the null hypothesis at the 5% level of significance.
Similarly, if we consider the 10% level of significance, then it implies that the probability of getting a sample mean as extreme as the one we have observed under the null hypothesis is less than 10%. Hence, if we can reject the null hypothesis at the 5% level of significance, then we can also reject it at the 10% level of significance. Therefore, if we reject H₀ with a given H₁ at a higher level of significance, we will surely reject H₀ at a lower level of significance.
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Answer the following question regarding the normal
distribution:
If X has a normal distribution with mean µ = 9 and variance
σ2 = 4, find P(X2− 2X ≤ 8).
The value of P(X2− 2X ≤ 8) is 0.0062
Given that X has a normal distribution with a mean µ = 9 and variance σ² = 4.
To find the probability, P(X² - 2X ≤ 8), let us standardize the normal random variable X.
It follows a standard normal distribution, N(0, 1).Standardizing X:(X - µ)/σ = (X - 9)/2
Therefore, P(X² - 2X ≤ 8) can be re-written as:P((X-1)² - 1 ≤ 9)
Now, P((X-1)² - 1 ≤ 9) can be transformed into the following:
P(|X-1| ≤ 3), which is the same as:P(-3 ≤ X - 1 ≤ 3)
Therefore,
P(-3 ≤ X - 1 ≤ 3) = P(X ≤ 4) - P(X ≤ -2)
P(X ≤ 4) = P(Z ≤ (4-9)/2) = P(Z ≤ -2.5) = 0.0062
P(X ≤ -2) = P(Z ≤ (-2-9)/2) = P(Z ≤ -5.5) = 0
Hence,
P(-3 ≤ X - 1 ≤ 3) = P(X ≤ 4) - P(X ≤ -2)= 0.0062 - 0 = 0.0062
Therefore, P(X² - 2X ≤ 8) ≈ 0.0062
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Write the ratio as a fraction in simplest form, with whole numbers in the numerator and denominator. 40:5 ? 0 DO X G
A fraction is a mathematical unit used to express a portion of a whole or a ratio of two quantities. The numerator is the number above the line, and the denominator is the number below the line. These two numbers are separated by a horizontal line.'
We need to write it as a fraction in simplest form with whole numbers in the numerator and denominator. To do that, we divide both terms by the greatest common factor of the two terms:40 and 5 has the greatest common factor of
5:40 ÷ 5 = 8, and
5 ÷ 5 = 1.
Therefore, the ratio 40:5 can be written as a fraction in simplest form as:
8:1 or 8/1
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Consider the following: (If an answer does not exist, enter DNE:) f(x) x3 3x2 _ 8x + 3 Find the interval(s) on which f is concave Up. (Enter your answer using interval notation ) Find the interval(s) on which f is concave down: (Enter your answer using interval notation:) Find the inflection point f f. (x, Y) =
The inflection point of f(x) is (1, -6)..To determine the intervals on which the function f(x) = x^3 - 3x^2 - 8x + 3 is concave up or concave down, we need to find the second derivative and analyze its sign.
First, let's find the first and second derivatives of f(x): f'(x) = 3x^2 - 6x - 8, f''(x) = 6x - 6, To find the intervals of concavity, we need to determine where the second derivative is positive (concave up) or negative (concave down). Setting f''(x) = 0: 6x - 6 = 0, 6x = 6, x = 1. Now we can analyze the sign of the second derivative in different intervals: For x < 1: Substitute a value less than 1 into the second derivative, e.g., x = 0: f''(0) = 6(0) - 6 = -6. The second derivative is negative, indicating concave down.
For x > 1: Substitute a value greater than 1 into the second derivative, e.g., x = 2: f''(2) = 6(2) - 6 = 6. The second derivative is positive, indicating concave up. Therefore, we have: Interval of concavity: (-∞, 1) (concave down) and (1, +∞) (concave up). To find the inflection point, we need to check where the concavity changes. Since we found that the concavity changes at x = 1, the inflection point of the function f(x) is (1, f(1)). To find the y-coordinate of the inflection point, substitute x = 1 into the original function: f(1) = (1)^3 - 3(1)^2 - 8(1) + 3 = -6. Therefore, the inflection point of f(x) is (1, -6).
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Given the following sets of data: (25pts) Set A: 14, 16, 18, 20, 22, 24, 26, 28, 30 Set B 14, 18, 20, 22, 24, 24, 24, 26, 26 (a) What is the RANGE, VARIANCE AND STANDARD DEVIATION of each set: (b) Which of the two sets is more variable or spread out? Answers: (a) Set A Range Variance, S? Standard Deviation, S Set B Range Variance, S? Standard Deviation, S (b)
The range of Set A is 16, Set B is 12. The variance of Set A is approximately 18.89, Set B is approximately 10.22. The standard deviation of Set A is approximately 4.35, Set B is approximately 3.20. Set A is more variable or spread out than Set B.
What are the range, variance, and standard deviation of Set A and Set B, and which set is more variable or spread out?For Set A:
Range: The range is calculated by subtracting the smallest value from the largest value. Range = 30 - 14 = 16. Variance: To calculate the variance, we need to find the mean of the set first. The mean of Set A is (14+16+18+20+22+24+26+28+30)/9 = 22. The variance is the average of the squared differences between each value and the mean. Variance = ((14-22)² + (16-22)² + ... + (30-22)²)/9 ≈ 18.89. Standard Deviation: The standard deviation is the square root of the variance. Standard Deviation (S) = √(18.89) ≈ 4.35.For Set B:
Range: The range is calculated by subtracting the smallest value from the largest value. Range = 26 - 14 = 12.Variance: To calculate the variance, we need to find the mean of the set first. The mean of Set B is (14+18+20+22+24+24+24+26+26)/9 = 22. The variance is the average of the squared differences between each value and the mean. Variance = ((14-22)² + (18-22)² + ... + (26-22)²)/9 ≈ 10.22. Standard Deviation: The standard deviation is the square root of the variance. Standard Deviation (S) = √(10.22) ≈ 3.20.(b) To determine which set is more variable or spread out, we compare the ranges, variances, and standard deviations of Set A and Set B. Set A has a larger range (16 > 12), a larger variance (18.89 > 10.22), and a larger standard deviation (4.35 > 3.20) compared to Set B. Therefore, Set A is more variable or spread out than Set B.
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Please state the general framework of local optimization methods. Point out a potential problem of this framework and suggest a way to fix it.
The general framework of local optimization methods consists of an iterative process that finds a local minimum. In these methods, the current estimate of the solution is adjusted according to a certain rule.
The process is continued until the change in the objective function becomes small enough or a predefined stopping criterion is met.Local optimization methods usually begin with an initial guess. Then, they iteratively refine the guess. Each iteration is aimed at finding a new point in the solution space. The point should be better than the previous one according to some objective function. This objective function is to be minimized.
The objective function is to be minimized. The potential problem of this framework is that local optimization methods may get stuck in a local minimum. They may not be able to find the global minimum. One way to fix this problem is to use a global optimization method.
A global optimization method can explore the solution space more thoroughly to find the global minimum.
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Which of the following is not a valid point of companion between histograms and graph? A. Histograms always have vertical bars, while bar graphs can be either horizontal or vertical B. The bars in a histogram touch, but the bars in a bar graph do not have to touch C. Histograms represent quantitative data, while bar graphs representative qualitative data d. The width of the bars of a histogram is meaningful while the width at the bars in a bar graph is not
The option that is not a valid point of comparison between histograms and graphs is: C. Histograms represent quantitative data, while bar graphs represent qualitative data.
Histograms are a way of displaying data in a graph that gives an idea of the frequency distribution of that data.
It is a graphical representation of numerical data that is divided into segments or bins.
They are a sort of bar graph where the bars represent the frequency distribution of the data.
How do histograms work?
Histograms represent the frequency distribution of data in a visual format.
It is done by dividing the data into segments and plotting their frequency distribution using vertical bars.
The bars' height is proportional to the number of data points that fall within that range, while the bars' width represents the range of values the data encompasses.
Additionally, the bars in histograms touch since they represent a continuous range of values, whereas in bar graphs, they don't have to.
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The National Operations Research Center polled a sample of 92 people aged 18 - 22 in the year 2002, asking them how many hours per week they spent on the internet. The sample mean was 7.38 with a sample standard deviation of 12.83. A second sample of 123 people aged 18 - 22 was taken in the year 2004. For this sample, the mean was 8.20 and the standard deviation waw 9.84. a. Can you conclude that the mean number of hours per week increased between 2002 and 2004? (10 points) State the null and alternative hypotheses. Compute the test statistic correctly labeled tor z. ii. (10 points) Compute a p value and state your conclusion in context. b. (10 points) Construct a 95% confidence interval for the mean increase in hours spent on the internet from 2002 to 2004. c. (10 points) Interpret the confidence interval in part b intwo ways. d. (10 points) Using the same sample size for both samples, find the necessary sample size needed to achieve a 95% confidence level with a margin of error of 2 hours.
The alternate hypothesis assumes that the mean number of hours per week spent on the internet decreased between 2002 and 2004.
How to find?a. 2. Compute the test statistic correctly labeled tor z.
$Z=\frac{\left(\bar{x}_{1}-\bar{x}_{2}\right)-\left(\mu_{1}-\mu_{2}\right)}{\sqrt{\frac{\left(\sigma_{1}^{2}\right)}{n_{1}}+\frac{\left(\sigma_{2}^{2}\right)}{n_{2}}}}$ $\bar{x}_{1}
=7.38, \bar{x}_{2}
=8.20, \sigma_{1}
=12.83, \sigma_{2}
=9.84, n_{1}
=92, n_{2}
=123$ $Z
=\frac{\left(8.20-7.38\right)-\left(0\right)}{\sqrt{\frac{\left(12.83^{2}\right)}{92}+\frac{\left(9.84^{2}\right)}{123}}}$ $
=-0.485$
ii. Compute a p-value and state your conclusion in context.
At the $\alpha=0.05$ significance level, the null hypothesis will be rejected if the p-value is less than 0.05.
There is no statistically significant evidence to suggest that the mean number of hours spent on the internet per week has increased between 2002 and 2004.
b. Construct a 95 percent confidence interval for the mean increase in hours spent on the internet from 2002 to 2004.$\bar{x}_{1}=7.38, \bar{x}_{2}
=8.20, s_{1}
=12.83, s_{2}
=9.84, n_{1}
=92, n_{2}
=123$ .
We'll start by calculating the point estimate:
$\bar{x}_{2}-\bar{x}_{1}
=8.20-7.38
=0.82$ $s_{p}=\sqrt{\frac{\left(n_{1}-1\right)\left(s_{1}^{2}\right)+\left(n_{2}-1\right)\left(s_{2}^{2}\right)}{n_{1}+n_{2}-2}}$ $=\sqrt{\frac{\left(92-1\right)
\left(12.83^{2}\right)+\left(123-1\right)\left(9.84^{2}\right)}
{92+123-2}}$ $=11.467$
$t_{\frac{\alpha}{2}, n_{1}+n_{2}-2}
=t_{0.025, 213}=1.972$
The margin of error: $E=t_{\frac{\alpha}{2}, n_{1}+n_{2}-2} \cdot s_{p} \sqrt{\frac{1}{n_{1}}+\frac{1}{n_{2}}}$ $=1.972 \cdot 11.467 \cdot \sqrt{\frac{1}{92}+\frac{1}{123}}$ $=4.07$ .
Confidence interval: $\left(\bar{x}_{2}-\bar{x}_{1}-E, \bar{x}_{2}-\bar{x}_{1}+E\right)$ $=\left(0.82-4.07, 0.82+4.07\right)$ $
=(-3.25, 4.89)$
c. Interpret the confidence interval in part b in two ways.We are 95 percent confident that the true mean increase in hours spent on the internet per week from 2002 to 2004 is between -3.25 and 4.89 hours.
We can conclude that the difference between the mean number of hours spent on the internet per week between 2002 and 2004 is not significant.
d. Using the same sample size for both samples, find the necessary sample size needed to achieve a 95% confidence level with a margin of error of 2 hours.
We're going to use the margin of error formula:
$E=z_{\frac{\alpha}{2}} \cdot \frac{s}{\sqrt{n}}$ $n
=\frac{z_{\frac{\alpha}{2}}^{2} \cdot s^{2}}{E^{2}}$.
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