Answer:
This Statement is True.
Check Explanation for why it is true.
Step-by-step explanation:
The sampling distribution of sample means arises when random samples are drawn from the population distribution and their respective means are computed and put together to form a distribution. Hence, the curve of this sampling distribution of sample means will show how the sample means are distributed. Hence, this statement is true.
Hope this Helps!!!
Help me pls I need help
Answer:
C
Step-by-step explanation:
If two lines are parallel, their slopes are the same.
Since the slope of line l is 4/9, this means that the slope of line m must also be 4/9.
Answer:
C. 4/9
Step-by-step explanation:
Parallel lines have equal slopes.
Since line l and line m are parallel, then their slopes must be the same.
[tex]m_{l} =m_{m}[/tex]
We know that the slope of line l is 4/9
[tex]\frac{4}{9} = m_{m}[/tex]
Line l has a slope of 4/9, therefore line m must also have a slope of 4/9.
The correct answer is C. 4/9
What is the value of x in the figure above
the value of x is 115°.
hope its helpful to uh..
In a recent study of 42 eighth graders, the mean number of hours per week that they watched television was 19.6. Assume the population standard deviation is 5.8 hours. Find the 98% confidence interval for the population mean.
a. (17.5, 21.7)
b. (14.1, 23.2)
c. (18.3, 20.9)
d. (19.1, 20.4)
Answer:
[tex]19.6-2.42\frac{5.8}{\sqrt{42}}=17.43[/tex]
[tex]19.6+2.42\frac{5.8}{\sqrt{42}}=21.77[/tex]
And the best option for this case would be:
a. (17.5, 21.7)
Step-by-step explanation:
Information given
[tex]\bar X= 19.6[/tex] represent the sample mean
[tex]\mu[/tex] population mean
[tex]\sigma= 5.8[/tex] represent the population deviation
n=42 represent the sample size
Confidence interval
The confidence interval for the mean is given by the following formula:
[tex]\bar X \pm t_{\alpha/2}\frac{s}{\sqrt{n}}[/tex] (1)
The degrees of freedom, given by:
[tex]df=n-1=42-1=41[/tex]
Since the Confidence is 0.98 or 98%, the significance would be [tex]\alpha=0.02[/tex] and [tex]\alpha/2 =0.1[/tex], and the critical value would be [tex]t_{\alpha/2}=2.42[/tex]
Replacing we got:
[tex]19.6-2.42\frac{5.8}{\sqrt{42}}=17.43[/tex]
[tex]19.6+2.42\frac{5.8}{\sqrt{42}}=21.77[/tex]
And the best option for this case would be:
a. (17.5, 21.7)
Answer:
The 98% confidence interval for the population mean is between 17.5 hours and 21.7 hours.
Suppose you pick 4 cards randomly from a well-shuffled standard deck of 52 playing cards. The probability that you draw the 2, 4, 6, and 8 of spades in that order is
Answer: 1/52 x 1/51 x 1/50 x 1/49
= 1/ 6,497,400
Step-by-step explanation:
pls help help help hepl
Answer:
C
Step-by-step explanation:
undefined slope means tat the denominator=0 in the equation
m=y2-y1/x2-x1
A: m=-1-1/1+1=-2
B;2-2/2+2=0
C: 3+3/-3+3 = 6/0 undefined
D: 4+4/4+4=1
In her backyard, Mary is planting rows of tomatoes. To plant a row of tomatoes, mary needs 20/13 square feet. There are 40 square feet in Mary's backyard, so how many rows of tomatoes can mary plant??
Answer:
26 rows
Step-by-step explanation:
[tex]number \: of \: rows \\ = \frac{40}{ \frac{20}{13} } \\ \\ = \frac{40 \times 13}{20} \\ \\ = 2 \times 13 \\ \\ = 26 \: [/tex]
5c + 16.5 = 13.5 + 10c
Answer:
Hello!
________________________
5c + 16.5 = 13.5 + 10c
Exact Form: c = 3/5
Decimal Form: c = 0.6
Step-by-step explanation: Isolate the variable by dividing each side by factors that don't contain the variable.
Hope this helped you!
Answer:
3000+3d=noods
Step-by-step explanation:
The function f(x) = 2x^3 + 3x^2 is:
(a) even
(b) odd
(c) neither
(d) even and odd
Answer:
neither
Step-by-step explanation:
First we must determine if both x and -x are in the domain of the function
since it is a polynomial function our first condition is satisfied
Then we should calculate the image of -x :
2x(-x)^3 + 3*(-x)² = -2x^3+3x²
it is not equal to f(x) nor -f(x)
The graph of y =ex is transformed as shown in the graph below. Which equation represents the transformed function?
Answer:
B. e^x+3
Step-by-step explanation:
Y=e^x
the graph is moving 3 units up
y= y+3
y=e^x+3
answer = y=e^x+3
Answer: B
Step-by-step explanation:
Follow the properties of the equality given for the steps to solve the following equation:
-3(x-4)+5=-x-3
(answers and steps in photo)
Answer:
Step-by-step explanation:
-3x+12+5= -x-3 -3x+17 = -x-317 = 2x-320 =2xx=10How do you write 0.0026 in scientific notation? ___× 10^____
Answer:
It's written as
[tex]2.6 \times {10}^{ - 3} [/tex]
Hope this helps you
Answer:
2.6 × 10⁻³
Step-by-step explanation:
To write a number in scientific notation, move the decimal to the right or left until you reach a number that is 1 or higher.
In the decimal 0.0026, the first number that is 1 or higher is 2.
0.0026 ⇒ 2.6
When trying to figure out the exponent, here are some things to keep in mind:
- when you move the decimal to the right, the exponent is negative
- when you move the decimal to the left, the exponent is positive
You moved the decimal to the right three places. So the exponent will be -3.
The result is 2.6 × 10⁻³.
Hope this helps. :)
The average daily rainfall for the past week in the town of Hope Cove is normally distributed, with a mean rainfall of 2.1 inches and a standard deviation of 0.2 inches. If the distribution is normal, what percent of data lies between 1.9 inches and 2.3 inches of rainfall? a) 95% b) 99.7% c) 34% d) 68%
Answer:
D
Step-by-step explanation:
We calculate the z-score for each
Mathematically;
z-score = (x-mean)/SD
z1 = (1.9-2.1)/0.2 = -1
z2 = (2.3-2.1)/0.2 = 1
So the proportion we want to calculate is;
P(-1<x<1)
We use the standard score table for this ;
P(-1<x<1) = P(x<1) -P(x<-1) = 0.68269 which is approximately 68%
Answer:
68
Step-by-step explanation:
The valve was tested on 250 engines and the mean pressure was 7.3 pounds/square inch (psi). Assume the population standard deviation is 0.8. The engineer designed the valve such that it would produce a mean pressure of 7.2 psi. It is believed that the valve does not perform to the specifications. A level of significance of 0.05 will be used. Find the value of the test statistic. Round your answe
Answer:
Step-by-step explanation:
We would set up the hypothesis test. This is a test of a single population mean since we are dealing with mean
For the null hypothesis,
H0: µ = 7.2
For the alternative hypothesis,
H1: µ ≠ 7.2
This is a two tailed test.
Since the population standard deviation is given, the test statistic would be the z score determined from the normal distribution table. The formula is
z = (x - µ)/(σ/√n)
Where
x = sample mean
µ = population mean
σ = population standard deviation
n = number of samples
From the information given,
µ = 7.2
x = 7.3
σ = 0.8
n = 250
z = (7.3 - 7.2)/(0.8/√250) = 1.976
Test statistic is 1.976
As part of a larger project to study the behavior of stressed-skin panels, a structural component being used extensively in North America, an article reported on various mechanical properties of Scotch pine lumber specimens. Data on the modulus of elasticity (MPa) obtained 1 minute after loading in a certain configuration and 4 weeks after loading for the same lumber specimens is presented here.
Observatio 1 min 4 Week Difference
1 16,620 9,110 1380
2 17,300 13,250 3370
3 15,480 14,720 2580
4 12,970 12,740 2740
5 17,260 10,120 2850
6 13,400 14,570 2690
7 13,900 11,220 2180
8 13,630 11,100 2800
9 13,260 11,420 2210
10 14,370 10,910 2350
11 11,700 12,110 2260
12 15,470 8,620 3080
13 17,840 12,590 2880
14 14,070 15,090 2750
15 14,760 10,550 3520
Required:
Calculate and interpret an upper confidence bound for the true average difference between 1-minute modulus and 4-week modulus; first check the plausibility of any necessary assumptions. (Use α = 0.05. Round your answer to the nearest whole number.)
Answer:
The upper confidence bound for the true average difference between 1-minute modulus and 4-week modulus is 2933.82.
Step-by-step explanation:
Compute the mean difference and standard deviation of the difference as follows:
[tex]\bar d=\frac{1}{n}\sum d_{i}=\frac{1}{15}\times [1380+3370+2580+...+3520]=2642.67\\\\S_{d}=\sqrt{\frac{1}{n-1}\sum (d_{i}-\bar d)^{2}}\\=\sqrt{\frac{1}{15-1}[(1380-2642.67)^{2}+(3370-2642.67)^{2}+...}=525.69[/tex]
The degrees of freedom is:
df = n - 1
= 15 - 1
= 14
Th critical value of t is:
[tex]t_{\alpha/2, (n-1)}=t_{0.05/2, 14}=2.145[/tex]
*Use a t-table.
Compute the upper confidence bound for the true average difference between 1-minute modulus and 4-week modulus as follows:
[tex]\text{Upper Confidence Bound}=\bar d+t_{\alpha/2, (n-1)}\cdot \frac{S_{d}}{\sqrt{n}}[/tex]
[tex]=2642.67+2.145\cdot \frac{525.69}{\sqrt{15}}\\\\=2642.67+291.15\\\\=2933.82[/tex]
Thus, the upper confidence bound for the true average difference between 1-minute modulus and 4-week modulus is 2933.82.
Solve the quadratic equation x2 + 14x = 51 by completing the square.
Question 3 options:
A)
x = –17, x = –3
B)
x = –17, x = 3
C)
x = 3, x = 17
D)
x = –3, x = 17
Answer:
B
Step-by-step explanation:
Given
x² + 14x = 51
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(7)x + 49 = 51 + 49 , that is
(x + 7)² = 100 ( take the square root of both sides )
x + 7 = ± [tex]\sqrt{100}[/tex] = ± 10 ( subtract 7 from both sides )
x = - 7 ± 10
Thus
x = - 7 - 10 = - 17
x = - 7 + 10 = 3
What is the greatest common factor of 36 and 44?
Answer:
GCF - 4
Step-by-step explanation:
36 - 1, 2, 3, 4, 6, 9, 12, 18, 36
44 - 1, 2, 4, 11, 44
Hope this helps! :)
What is the surface area of this regular pyramid? A. 230 in2 B. 304 in2 C. 480 in2 D. 544 in2
Answer:
B: 304in^2
Step-by-step explanation:
One triangle face: (8)(15) ÷ 2 = 60
Four triangle faces: 60 x 4 = 240
Bottom Face: (8)(8) = 64
Total Surface Area: Four triangle faces + Bottom Face
Total Surface Area: 240 + 64
Total Surface Area: 304in^2
divide 15 root 20 by 6 root 125
Answer:
15√20/6√125
=√20/√5
=2
Step-by-step explanation:
In a lecture of 100 students, there are 29 women and 23 men. Out of these students, 4 are teachers and 24 are either men or teachers. Find the number of women teachers attending the lecture.
Answer:
1 woman Teacher
Step-by-step explanation:
We proceed as follows;
Let W and M represent the set of women and men respectively , and T represent teachers
from the information given in the question we have
n(W)=29
n(M)=23
n(T)=4
n(M U T)=24
Mathematically;
n(MUT)=n(M)+n(T)-n(MnT)
24=23+4-n(Mn T)
n(MnT)=3
that is number of men teachers is 3,
so out of 4 teachers there are 3 men ,
and remaining 1 is the women teacher .
so the number of women teachers attending the lecture is 1
Consider the accompanying matrix as the augmented matrix of a linear system. State in words the next two elementary row operations that should be performed in the process of solving the system.
(1 -4 4 0 -2
0 2 -6 0 5
0 0 1 2 - 4
0 0 4 5 -1]
(Type an integer or a simplified fraction)
A. Replace row 4 by its sum with - 4 times row 3.
(Type an integer or a simplified fraction)
B. Replace row 2 by its sum with times row 4.
(Type an integer or a simplified fraction.)
C. Interchange row 3 and row 2.
Answer:
The correct option is (A)
A. Replace row 4 by its sum with - 4 times row 3.
[tex]\left[\begin{array}{ccccc}1&-4&4&0&-2\\0&2&-6&0&5\\0&0&1&2&-4\\0&0&0&-3&15\end{array}\right][/tex]
w = 8
x = 17/2
y = 6
z = -5
Step-by-step explanation:
The given matrix is
[tex]\left[\begin{array}{ccccc}1&-4&4&0&-2\\0&2&-6&0&5\\0&0&1&2&-4\\0&0&4&5&-1\end{array}\right][/tex]
To solve this matrix we need to create a zero at the 4th row and 3rd column which is 4 at the moment.
Multiply 3rd row by -4 and add it to the 4th row.
Mathematically,
[tex]R_4 = R_4 - 4R_3[/tex]
So the correct option is (A)
A. Replace row 4 by its sum with - 4 times row 3.
So the matrix becomes,
[tex]\left[\begin{array}{ccccc}1&-4&4&0&-2\\0&2&-6&0&5\\0&0&1&2&-4\\0&0&0&-3&15\end{array}\right][/tex]
Now the matrix may be solved by back substitution method.
Bonus:
The solution is given by
Eq. 1
-3z = 15
z = -15/3
z = -5
Eq. 2
y + 2z = -4
y + 2(-5) = -4
y - 10 = -4
y = -4 + 10
y = 6
Eq. 3
2x - 6y + 0z = 5
2x - 6(6) = 5
2x - 12 = 5
2x = 12 + 5
2x = 17
x = 17/2
Eq. 4
w - 4x + 4y + 0z = -2
w - 4(17/2) + 4(6) = -2
w - 34 + 24 = -2
w - 10 = -2
w = -2 + 10
w = 8
What is the solution of (4x-16)1/3=36
(4x-16)/3 = 36
4x-16 = 108
4x = 108+16
4x = 124
x = 124/4
x = 31
Answer:
x = 31
Step-by-step explanation:
=> [tex](4x-16)\frac{1}{3} = 36[/tex]
Multiplying 3 to both sides
=> [tex]4x-16 = 36*3[/tex]
=> 4x-16 - 108
Adding 16 to both sides
=> 4x = 108+16
=> 4x = 124
Dividing both sides by 4
=> x = 31
Maya is solving the quadratic equation by completing the square. 4x2 + 16x + 3 = 0 What should Maya do first?
Maya should Isolate the variable x² option (A) Isolate the variable x² is correct.
What is a quadratic equation?Any equation of the form [tex]\rm ax^2+bx+c=0[/tex] where x is variable and a, b, and c are any real numbers where a ≠ 0 is called a quadratic equation.
As we know, the formula for the roots of the quadratic equation is given by:
[tex]\rm x = \dfrac{-b \pm\sqrt{b^2-4ac}}{2a}[/tex]
The complete question is:
Maya is solving the quadratic equation by completing the What should Maya do first? square.
4x² + 16x + 3 = 0
Isolate the variable x².Subtract 16x from both sides of the equation.Isolate the constant.Factor 4 out the variable terms.We have a quadratic equation:
4x² + 16x + 3 = 0
To make the perfect square
Maya should do first:
Isolate the variable x²
To make the coefficient of x² is 1.
4(x² + 4x + 3/4) = 0
x² + 4x + 3/4 = 0
x² + 4x + 2² - 2² + 3/4 = 0
(x + 2)² - 4 + 3/4 = 0
(x + 2)² = 13/4
x + 2 = ±√(13/4)
First, take the positive and then the negative sign.
x = √(13/4) - 2
x = -√(13/4) - 2
Thus, Maya should Isolate the variable x² option (A) Isolate the variable x² is correct.
Learn more about quadratic equations here:
brainly.com/question/2263981
#SPJ5
Question
An airplane is traveling at a constant speed of 585 miles per hour. How many feet does it travel in 6 seconds? Remember
that 1 mile is 5280 feet.
Convert the 6 seconds to hours:
5 seconds x x 1/60 ( minutes per seconds) x 1/60 (Hours per minute) = 6/3600 = 1/600 hours.
Distance = speed x time
Distance = 585 x 1/600 = 585/600 = 0.975 miles
Convert miles to feet:
0.975 x 5280 = 5,148 feet
The plane traveled 5,148 feet in 6 seconds.
Need Help With This
Answer/Step-by-step explanation:
Let x = 4 (you and 3 friends)
Ticket cost per head = $5.50
Drink cost per head = $2.50
Popcorn cost per head = $4.00
Expression representing total amount of money spent = $5.50(x) + $2.50(x) + $4.00(x)
Evaluate the expression by plugging in the value of x = 4
Total amount of money spent = $5.50(4) + $2.50(4) + $4.00(4)
= $22 + $10 + $16 = $48
Total amount of money spent = $48
Select two ratios that are equivalent to 7:6
Two ratios that are equal to 7:6 are 14:12 and 21:18, as they are the same, but 7 and 6 are multiplied by the same number (2 in the first, and 3 in the second.)
A study of the amount of time it takes a mechanic to rebuild the transmission for a 2010 Chevrolet Colorado shows that the mean is 8.4 hours and the standard deviation is 1.8 hours. If 40 mechanics are randomly selected, find the probability that their mean rebuild time is less than 8.9 hours.
Answer:
96.08% probability that their mean rebuild time is less than 8.9 hours.
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal probability distribution
When the distribution is normal, we use the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
In this question:
[tex]\mu = 8.4, \sigma = 1.8, n = 40, s = \frac{1.8}{\sqrt{40}} = 0.2846[/tex]
Find the probability that their mean rebuild time is less than 8.9 hours.
This is the pvalue of Z when X = 2.9.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{2.9 - 2.4}{0.2846}[/tex]
[tex]Z = 1.76[/tex]
[tex]Z = 1.76[/tex] has a pvalue of 0.9608
96.08% probability that their mean rebuild time is less than 8.9 hours.
y and z are whole numbers y<70 z 60 work out the largest possible value of y and z
Answer:
a) 12
b) 129
Step-by-step explanation:
a)
[tex]w, x \in \mathbb{Z}_{\ge 0}[/tex]
[tex]w>50\\x<40[/tex]
For the smallest value of [tex]w-x[/tex], we gotta figure out the smallest value for w and the highest value for x.
[tex]w>50 \Rightarrow \text{ smallest value is } 51[/tex]
For [tex]x[/tex], once [tex]-(-x)=x[/tex], we conclude that [tex]x[/tex] cannot be negative and therefore, [tex]x=39[/tex].
[tex]51-39=12[/tex]
b)
[tex]y, z \in \mathbb{Z}_{\ge 0}[/tex]
[tex]y<70\\z\leq 60[/tex]
For the largest value of [tex]y+z[/tex], we gotta figure out the highest value for y and z.
[tex]y<70 \Rightarrow \text{ highest value is } 69[/tex]
[tex]z\leq 60 \Rightarrow \text{ highest value is } 60[/tex]
[tex]y+z=69+60=129[/tex]
Andrew plans to retire in 36 years. He plans to invest part of his retirement funds in stocks, so he seeks out information on past returns. He learns that over the entire 20th century, the real (that is, adjusted for inflation) annual returns on U.S. common stocks had mean 8.7% and standard deviation 20.2%. The distribution of annual returns on common stocks is roughly symmetric, so the mean return over even a moderate number of years is close to Normal.
(a) What is the probability (assuming that the past pattern of variation continues) that the mean annual return on common stocks over the next 36 years will exceed 11%?
(b) What is the probability that the mean return will be less than 5%?
Answer:
a) 24.82% probability that the mean annual return on common stocks over the next 36 years will exceed 11%
b) 13.57% probability that the mean return will be less than 5%
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
Normal probability distribution
When the distribution is normal, we use the z-score formula.
In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the zscore of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
Central Limit Theorem
The Central Limit Theorem estabilishes that, for a normally distributed random variable X, with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]s = \frac{\sigma}{\sqrt{n}}[/tex].
For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.
In this question:
[tex]\mu = 8.7, \sigma = 20.2, n = 36, s = \frac{20.2}{\sqrt{36}} = 3.3667[/tex]
(a) What is the probability (assuming that the past pattern of variation continues) that the mean annual return on common stocks over the next 36 years will exceed 11%?
This is 1 subtracted by the pvalue of Z when X = 11.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{11 - 8.7}{3.3667}[/tex]
[tex]Z = 0.68[/tex]
[tex]Z = 0.68[/tex] has a pvalue of 0.7518
1 - 0.7518 = 0.2482
24.82% probability that the mean annual return on common stocks over the next 36 years will exceed 11%
(b) What is the probability that the mean return will be less than 5%?
This is the pvalue of Z when X = 5.
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{5 - 8.7}{3.3667}[/tex]
[tex]Z = -1.1[/tex]
[tex]Z = -1.1[/tex] has a pvalue of 0.1357
13.57% probability that the mean return will be less than 5%
student throws 3 coins in the air. Find the probability that exactly 2 landed on heads, given that at least 2 landed on heads.
Step-by-step explanation:
Head(H) Tails(T)
Sample space is S (HHH,HHT,HTH,THH)
Event(HHT,HTH,THH)
so the probability is 3/4
Answer:
3/4
Step-by-step explanation:
Type 11/5 in the simplest form
Answer:
[tex]2\frac{1}{5}[/tex]
Step-by-step explanation:
11 ÷ 5 = 2 R 1 → [tex]2\frac{1}{5}[/tex]
Hope this helps! :)