Answer:
The 99% confidence interval estimate of the percentage of girls born is between 85.46% and 94.54%.
Usually, babies are equally as likely to be boys or girls. Here, it is desired to increase the probability of conceiving a girl, which is achieved, considering the lower bound of the confidence interval is considerably above 50%.
Step-by-step explanation:
Confidence interval for the proportion:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the zscore that has a pvalue of [tex]1 - \frac{\alpha}{2}[/tex].
For this problem, we have that:
[tex]n = 290, \pi = \frac{261}{290} = 0.9[/tex]
99% confidence level
So [tex]\alpha = 0.01[/tex], z is the value of Z that has a pvalue of [tex]1 - \frac{0.01}{2} = 0.995[/tex], so [tex]Z = 2.575[/tex].
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.9 - 2.575\sqrt{\frac{0.9*0.1}{290}} = 0.8546[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.9 + 2.575\sqrt{\frac{0.9*0.1}{290}} = 0.9454[/tex]
Percentage:
Proportion multplied by 100.
0.8546*100 = 85.46%
0.9454*100 = 94.54%
The 99% confidence interval estimate of the percentage of girls born is between 85.46% and 94.54%.
Based on the result, does the method appear to be effective?
Usually, babies are equally as likely to be boys or girls. Here, it is desired to increase the probability of conceiving a girl, which is achieved, considering the lower bound of the confidence interval is considerably above 50%.
Choose the equation of the horizontal line that passes through the point (−5, 9). y = −5 y = 9 x = −5 x = 9
Answer:
y = 9
Step-by-step explanation:
Since we are trying to find a horizontal line, our line would have to be y = [a number]. That takes our x = -5 and x = 9 out as answer choices. We are left with y = -5 and y = 9. y = 9 is correct because the horizontal line is the y-values, and since in (-5, 9), our y-value is 9, our line is y = 9.
A square with side lengths of 3 cm is reflected vertically over a horizontal line of reflection that is 2 cm below the bottom edge of the square. What is the distance between the points C and C’? cm What is the perpendicular distance between the point B and the line of reflection? cm What is the distance between the points A and A’? cm
Answer:
a) 4 cm
b) 5 cm
c) 10 cm
Step-by-step explanation:
The side lengths of the reflected square are equal to the original, and the distance from the axis(2) also remains the same. From there, it is just addition.
Hope it helps <3
Answer:
A) 4
B) 5
C) 10
Step-by-step explanation:
edge2020
Eagle Outfitters is a chain of stores specializing in outdoor apparel and camping gear. They are considering a promotion that involves mailing discount coupons to all their credit card customers. This promotion will be considered a success if more than 10% of those receiving the coupons use them. Before going national with the promotion, coupons were sent to a sample of 100 credit card customers.
a. Develop hypotheses that can be used to test whether the population proportion of those
who will use the coupons is sufficient to go national.
b. The file Eagle contains the sample data. Develop a point estimate of the population
proportion.
c. Use αα= .05 to conduct your hypothesis test. Should Eagle go national with the
promotion?
Answer:
a) Alternative hypothesis: the use of the coupons is isgnificantly higher than 10%.
Null hypothesis: the use of the coupons is not significantly higher than 10%.
The null and alternative hypothesis can be written as:
[tex]H_0: \pi=0.1\\\\H_a:\pi>0.1[/tex]
b) Point estimate p=0.13
c) At a significance level of 0.05, there is not enough evidence to support the claim that the proportion of coupons use is significantly higher than 10%.
Eagle should not go national with the promotion as there is no evidence it has been succesful.
Step-by-step explanation:
The question is incomplete.
The sample data shows that x=13 out of n=100 use the coupons.
This is a hypothesis test for a proportion.
The claim is that the proportion of coupons use is significantly higher than 10%.
Then, the null and alternative hypothesis are:
[tex]H_0: \pi=0.1\\\\H_a:\pi>0.1[/tex]
The significance level is 0.05.
The sample has a size n=100.
The point estimate for the population proportion is the sample proportion and has a value of p=0.13.
[tex]p=X/n=13/100=0.13[/tex]
The standard error of the proportion is:
[tex]\sigma_p=\sqrt{\dfrac{\pi(1-\pi)}{n}}=\sqrt{\dfrac{0.1*0.9}{100}}\\\\\\ \sigma_p=\sqrt{0.0009}=0.03[/tex]
Then, we can calculate the z-statistic as:
[tex]z=\dfrac{p-\pi-0.5/n}{\sigma_p}=\dfrac{0.13-0.1-0.5/100}{0.03}=\dfrac{0.025}{0.03}=0.833[/tex]
This test is a right-tailed test, so the P-value for this test is calculated as:
[tex]\text{P-value}=P(z>0.833)=0.202[/tex]
As the P-value (0.202) is greater than the significance level (0.05), the effect is not significant.
The null hypothesis failed to be rejected.
At a significance level of 0.05, there is not enough evidence to support the claim that the proportion of coupons use is significantly higher than 10%.
I NEED HELP PLEASE THANKS!
Jenny is sitting on a sled on the side of a hill inclined at 15°. What force is required to keep the sled from sliding down the hill if the combined weight of Jenny and the sled is 90 pounds? (Show work)
Answer:
23.29 lbs
Step-by-step explanation:
The force on Jenny due to gravity can be resolved into components perpendicular to the hillside and down the slope. The down-slope force is ...
(90 lbs)sin(15°) ≈ 23.29 lbs
In order to keep Jenny in position, that force must be balanced by an up-slope force of the same magnitude.
Which equation should be used to find the volume of the figure?
V=1/3(10)(6)(12)
V=1/2(10)(6)(12)
V=1/3(10)(6)(13)
V=1/2(10)(6)(13)
Answer:
The answer is option 1.
Step-by-step explanation:
Given that the volume of pyramid formula is:
[tex]v = \frac{1}{3} \times base \: area \times height[/tex]
The base area for this pyramid:
[tex]base \: area = area \: of \: rectangle[/tex]
[tex]base \: area = 10 \times 6[/tex]
Then you have to substitute the following values into the formula:
[tex]let \: base \: area = 10 \times 6 \\ let \: height = 12[/tex]
[tex]v = \frac{1}{3} \times 10 \times 6 \times 12[/tex]
Answer:
A. V = 1/3 (10)(6)(12)
Step-by-step explanation:
Just took the test and got it right
pls help me pls pls
Answer:
B
Step-by-step explanation:
the slope of parallel lines are equal
Pls help me help me
Answer:
C.
Step-by-step explanation:
When two lines are parallel, their slopes are the same.
Since the slope of line l is 2/7, the slope of its parallel line m must also be 2/7.
The answer is C.
Answer:
C. 2/7
Step-by-step explanation:
Parallel lines are lines that have the same slopes.
We know that line l is parallel to line m.
Therefore, the slope of line l is equal to the slope of line m.
[tex]m_{l} =m_{m}[/tex]
We know that line l has a slope of 2/7.
[tex]\frac{2}{7} =m_{m}[/tex]
So, line m also has a slope of 2/7. The answer is C. 2/7
Compute the critical value z Subscript alpha divided by 2 that corresponds to a 86% level of confidence.
Answer:
z = 1.476
Step-by-step explanation:
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1-0.86}{2} = 0.07[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1-\alpha[/tex].
So it is z with a pvalue of [tex]1-0.07 = 0.93[/tex], so [tex]z = 1.476[/tex]
The answer is z = 1.476
Find a parabola with equation y = ax2 + bx + c that has slope 5 at x = 1, slope −11 at x = −1, and passes through the point (2, 18).
By "slope" I assume you mean slope of the tangent line to the parabola.
For any given value of x, the slope of the tangent to the parabola is equal to the derivative of y :
[tex]y=ax^2+bx+c\implies y'=2ax+b[/tex]
The slope at x = 1 is 5:
[tex]2a+b=5[/tex]
The slope at x = -1 is -11:
[tex]-2a+b=-11[/tex]
We can already solve for a and b :
[tex]\begin{cases}2a+b=5\\-2a+b=-11\end{cases}\implies 2b=-6\implies b=-3[/tex]
[tex]2a-3=5\implies 2a=8\implies a=4[/tex]
Finally, the parabola passes through the point (2, 18); that is, the quadratic takes on a value of 18 when x = 2:
[tex]4a+2b+c=18\implies2(2a+b)+c=10+c=18\implies c=8[/tex]
So the parabola has equation
[tex]\boxed{y=4x^2-3x+8}[/tex]
Using function concepts, it is found that the parabola is: [tex]y = 4x^2 - 3x + 14[/tex]
----------------------------
The parabola is given by:
[tex]y = ax^2 + bx + c[/tex]
----------------------------
Slope 5 at x = 1 means that [tex]y^{\prime}(1) = 5[/tex], thus:
[tex]y^{\prime}(x) = 2ax + b[/tex]
[tex]y^{\prime}(1) = 2a + b[/tex]
[tex]2a + b = 5[/tex]
----------------------------
Slope -11 at x = -1 means that [tex]y^{\prime}(-1) = -11[/tex], thus:
[tex]-2a + b = -11[/tex]
Adding the two equations:
[tex]2a - 2a + b + b = 5 - 11[/tex]
[tex]2b = -6[/tex]
[tex]b = -\frac{6}{2}[/tex]
[tex]b = -3[/tex]
And
[tex]2a - 3 = 5[/tex]
[tex]2a = 8[/tex]
[tex]a = \frac{8}{2}[/tex]
[tex]a = 4[/tex]
Thus, the parabola is:
[tex]y = 4x^2 - 3x + c[/tex]
----------------------------
It passes through the point (2, 18), which meas that when [tex]x = 2, y = 18[/tex], and we use it to find c.
[tex]y = 4x^2 - 3x + c[/tex]
[tex]18 = 4(2)^2 - 3(4) + c[/tex]
[tex]c + 4 = 18[/tex]
[tex]c = 14[/tex]
Thus:
[tex]y = 4x^2 - 3x + 14[/tex]
A similar problem is given at https://brainly.com/question/22426360
If Brooklyn College students have an IQ of 100, on average, with a standard deviation of 16 points, and I collect 48 BC Psychology students to see how Psych majors compare to all of BC, find the following:_______.
1. mu =
2. sigma =
3. mu _x bar =
4. sigma _x bar =
Answer:
1 [tex]\mu = 100[/tex]
2 [tex]\sigma = 16[/tex]
3 [tex]\mu_x = 100[/tex]
4 [tex]\sigma _{\= x } = 2.309[/tex]
Step-by-step explanation:
From the question
The population mean is [tex]\mu = 100[/tex]
The standard deviation is [tex]\sigma = 16[/tex]
The sample mean is [tex]\mu_x = 100[/tex]
The sample size is [tex]n = 48[/tex]
The mean standard deviation is [tex]\sigma _{\= x } = \frac{\sigma }{\sqrt{n} }[/tex]
substituting values
[tex]\sigma _{\= x } = \frac{16 }{\sqrt{48} }[/tex]
[tex]\sigma _{\= x } = 2.309[/tex]
Suppose that a certain brand of light bulb has a mean life of 450 hours and a standard deviation of 73 hours. Assuming the data are bell-shaped: (Show work to get full credit)
a. Would it be unusual for a light bulb to have a life span of 320 hours? 615 hours? Justify each response.
b. According to the Empirical Rule, 99.7% of the light bulbs have a lifetime between what two values?
c. Determine the percentage of light bulbs that will have a life between 304 and 596 hours.
Answer:
yes it is correct
Step-by-step explanation:
plz give brainliest.
The left and right page numbers of an open book are two consecutive integers whose sum is 389. Find these page numbers
Step-by-step explanation:
Maybe the page numbers can be 143 and 246
143 + 246 = 389
Answer:
194 and 195
Step-by-step explanation:
x = 1st page
x + 1 = 2nd page
x + x + 1 = 389
2x + 1 = 389
2x = 388
x = 194
x + 1 = 195
A statistics tutor wants to assess whether her remedial tutoring has been effective for her five students. She decides to conduct a related samples t-test and records the following grades for students prior to and after receiving her tutoring.
Tutoring
Before After
2.4 3.1
2.5 2.8
3.0 3.6
2.9 3.2
2.7 3.5
Test whether or not her tutoring is effective at a 0.05 level of significance. State the value of the test statistic. (Round your answer to three decimal places.)
t =
Compute effect size using estimated Cohen's d. (Round your answer to two decimal places.)
d =
Answer:
The test statistic value is, t = -5.245.
The effect size using estimated Cohen's d is 2.35.
Step-by-step explanation:
A paired t-test would be used to determine whether the remedial tutoring has been effective for the statistics tutor's five students.
The hypothesis can be defined as follows:
H₀: The remedial tutoring has not been effective, i.e. d = 0.
Hₐ: The remedial tutoring has been effective, i.e. d > 0.
Use Excel to perform the Paired t test.
Go to Data → Data Analysis → t-test: Paired Two Sample Means
A dialog box will open.
Select the values of the variables accordingly.
The Excel output is attached below.
The test statistic value is, t = -5.245.
Compute the effect size using estimated Cohen's d as follows:
[tex]\text{Cohen's d}=\frac{Mean_{d}}{SD_{d}}[/tex]
[tex]=\frac{0.54}{0.23022}\\\\=2.34558\\\\\approx 2.35[/tex]
Thus, the effect size using estimated Cohen's d is 2.35.
Four different digits from 1 to 9 are required to open a safe.
1. The sum of the digits is 20.
2. The first digit is greater than the third.
3. The second and fourth digits differ by at least 5.
4. Exactly two digits are squares.
5. The first and fourth digits add up to a prime number.
6. The fourth digit is the lowest.
Can you find the four-digit combination?
Answer: 5942
Step-by-step explanation:
Clue 4 states exactly two of the digits = 1, 4, or 9
Clue 1 leaves us with the following combinations:
1, 9, 2, 8
1, 9, 3, 7 eliminate by clue 5
4, 9, 2, 5
1, 4, 7, 8
Clue 5 directs us to the following order for 1,9,2,8
2 __ __ 1 --> 2981 or 2891 eliminate by clue 2
9 __ __ 8 --> 9128 or 9218 eliminate by clue 6
9 __ __ 2 --> 9182 or 9812 eliminate by clue 6
Clue 5 directs us to the following order for 4,9,2,5
5 __ __ 2 --> 5492 or 5942 eliminate 5492 by clue 2
9 __ __ 2 --> 9452 or 9542 eliminate by clue 3
Clue 5 directs us to the following order for 1,4,7,8
4 __ __ 1 --> 4781 or 4871 eliminate by clue 2
The only combination not eliminated is 5-9-4-2, which satisfies all six clues.
1) 5 + 9 + 4 + 2 = 20
2) 5 > 4
3) 9 - 2 > 5
4) 4 & 9 but not 1 are included
5) 5 + 2 = 7, which is a prime number
6) 2 < 5, 9, 4
What is the distance between (−11, −20) and (−11, 5)?
−25 units
−15 units
15 units
25 units
Answer:
IT'S NOT -15 FOR SUREEE
Step-by-step explanation:
I Believe it's 15
Quadrilateral W X Y Z is shown. Diagonals are drawn from point W to point Y and from point Z to point X and intersect at point C. The lengths of W C and C Y are congruent. Which best explains if quadrilateral WXYZ can be a parallelogram? WXYZ is a parallelogram because diagonal XZ is bisected. WXYZ is not necessarily a parallelogram because it is unknown if CZ = CY. WXYZ is a parallelogram because ZC + CX = ZX. WXYZ is not necessarily a parallelogram because it is unknown if WC = CY.
Answer: The answer is D
Step-by-step explanation:
Edge 2021
The true statement is (d) WXYZ is not necessarily a parallelogram because it is unknown if WC = CY.
What are quadrilaterals?Quadrilaterals are shapes with four sides
What are parallelograms?Parallelograms are quadrilaterals that have equal and parallel opposite sides
The quadrilateral is given as:
WXYZ
Also, we have:
WC = CY
The given parameters are not enough to determine if the quadrilateral is a parallelogram or not
Hence, the true statement is (d) WXYZ is not necessarily a parallelogram because it is unknown if WC = CY.
Read more about quadrilaterals and parallelograms at:
https://brainly.com/question/1190071
8716 no es divisible por 4
Answer:
False
Step-by-step explanation:
No esta verdad.
8716/4 = 2179 (divisible por 4)
There is a set of 100 obserations with a mean of 46 and a standard deviation of 0. What is the value of smallest obserstion in a set?
Answer:
Solution = 46
Step-by-step explanation:
I believe you meant standard deviation. Standard deviation is defined as the variation of the data set, or the differences between the values in this set. In order for the standard deviation to be 0, all values should be the same.
Now if the mean is 46, the smallest possible number of each value in the data set should be 46 as well. This is considering the mean is the average of the values, and hence any number of values in the data set being 46 will always have a mean of 46. Let me give you a demonstration -
[tex]Ex. [ 46, 46, 46 ], and, [46, 46, 46, 46, 46]\\Average = 46 + 46 + 46 / 3 = 46,\\Average = 46 + 46 + 46 + 46 + 46 / 5 = 46[/tex]
As you can see, the average is 46 in each case. This proves that a data set consisting of n number of values in it, each value being 46, or any constant value for that matter, always has a mean similar to the value inside the set, in this case 46. And, that the value of the smallest standard deviation is 46.
: Bobby's Burger Palace had its
grand opening on Tuesday,
They had 164 1/2 lb of ground
beef in stock. They had 18 1/4
Ib left at the end of the day.
Each burger requires 1/4 lb of
ground beef. How many
hamburgers did they sell?
What is the equation of the line that is parallel to the given line and passes through the point (12, -2)? A) y = -6/5x + 10 B) y= -6/5x + 12 C) y = -5/6x -10 D) y = 5/6x - 12
Answer:
D
Step-by-step explanation:
Parallel lines are those that have the same slope, or coefficient of x.
Here, let's calculate the slope of the given line. Slope is the difference in the y-coordinates divided by the difference in the x-coordinates, so given the two coordinates (12, 6) and (0, -4):
slope = m = (-4 - 6) / (0 - 12) = -10 / (-12) = 10/12 = 5/6
So the slope is 5/6. That means the equation we want should also have a slope of 5/6. Already, we can eliminate A, B, and C, leaving D as our answer. But, let's check.
The equation of a line can be written as [tex]y-y_1=m(x-x_1)[/tex], where m is the slope and [tex](x_1,y_1)[/tex] is the coordinates of a given point.
Here, our slope is 5/6 and our given point is (12, -2). So plug these in:
[tex]y-y_1=m(x-x_1)[/tex]
[tex]y-(-2)=(5/6)(x-12)[/tex]
[tex]y+2=\frac{5}{6} x-10[/tex]
[tex]y=\frac{5}{6} x-12[/tex]
This matches D, so we know that it's the correct answer.
~ an aesthetics lover
The answer is D I just took the test
A school is 16km due west of a school q.
What is the bearing of q from p?
Answer:
16 km due west
Step-by-step explanation:
The bearing of the school p from school q is 16 km due west.
To find the bearing of school q from school p, we have to find the direction that the school q is with respect to school p.
Since p is directly west of q, then it implies that q must be directly east of p.
We now know the direction.
Since the distance from q to p is exactly the same as the distance from p to q, then, the distance from p to q is 16 km.
Hence, the bearing of q from p is 16 km due west.
the bus fare in a city is $2.00. people who use the bus have the option of purchashing a monthly coupoun book is $20.00. with the copoun bok, the fare is reduced to $1.00 Determine the number of times in a month the bus be used so that the total monthly cost without the coupon book is the same as the total monthly cost with the coupon book
Answer:
but I can do it if you want but I don't you too too y u your help and you have time can you
Step-by-step explanation:
guy who was it that you are not going to be able to make it to the meeting tonight but I can tomorrow if you have time can you come to my house
pls help me hepl me
Answer:
b at most 199
Step-by-step explanation:so the total was 121 and there is a flat fee of 21.50 so you subtract that out and gat 99.5 since its .5 per mile its going to be divided giving 199 and that is the most she could have driven.
A farmer is tracking the number of soybeans his land is yielding each year. He finds that the function f(x) = −x2 + 20x + 100 models the crops in pounds per acre over x years. Find and interpret the average rate of change from year 10 to year 20.
Answer:
The farmer should expect to LOSE 10 pounds of soybeans per acre per year
Step-by-step explanation:
f(x)=-x^2 + 20x + 100
just find how many soybeans his land will yield (per acre) after 10 and 20 years:
After 10: 200 pounds of soybeans/acre
After 20: 100 pounds of soybeans/acre
Because 10 years have passed and they lost 100 pounds of soybean production per acre, the farmer should expect to lose 10 pounds of soybeans per acre per year (-10 pounds of soybeans per acre/year)
The surface area of an open-top box with length L, width W, and height H can be found using the
formula:
A = 2LH + 2WH + LW
Find the surface area of an open-top box with length 9 cm, width 6 cm, and height 4 cm.
Answer:
174 square cm
Step-by-step explanation:
2(9×4) + 2(6×4)+ 9×6
2(36) + 2(24) + 54
72 + 48 + 54
120 + 54
174
3. Your friend is solving a system of linear equations and finds the following solution:
0=5
What is the solution of the system? Explain your reasoning.
Answer:
No solution.
Step-by-step explanation:
Because the equations are combined but the final answers are not equal, the equations have no solution. This is because "no matter what value is plugged in for the variable, you will ALWAYS get a contradiction".
Hope this helps!
15 3/4 is what decimal
━━━━━━━☆☆━━━━━━━
▹ Answer
15.75
▹ Step-by-Step Explanation
3 ÷ 4 = .75
15 + .75 = 15.75
Hope this helps!
- CloutAnswers ❁
Brainliest is greatly appreciated!
━━━━━━━☆☆━━━━━━━
The steps to prove the Law of Sines with reference to ∆ABC are given. Arrange the steps in the correct order.
1). Draw a perpendicular from point A to side BC. Let AD = h
2). sin A = h/c and sin C = h/a
3). h = c Sin A, h = a sin C
4). c Sin A =a sin C
5). Divide both side by Sin A * Sin C
6). c Sin A/(Sin A * Sin C) =a sin C/(Sin A * Sin C)
7). c/sin C = a/Sin A
8). Similarly prove that, c/sin C = b/Sin B
9). c/sin C = b/Sin B = a/Sin A
correct on plato
Identify the slope and y-intercept of the line −2x+5y=−30.
Answer:
slope = 2/5 , y-intercept = -30
Step-by-step explanation:
-2x + 5y = -30
5y = 2x - 30
y = 2/5x - 6
we know that the general form is:
y = (slope)*x + (y- intercept)
so, from our equation, we can say that...
slope = 2/5
y- intercept = -30
The head of maintenance at XYZ Rent-A-Car believes that the mean number of miles between services is 3639 3639 miles, with a variance of 145,161 145,161 . If he is correct, what is the probability that the mean of a sample of 41 41 cars would differ from the population mean by less than 126 126 miles
Answer:
96.6% probability that the mean of a sample would differ from the population mean by less than 126 miles
Step-by-step explanation:
To solve this question, we need to understand the normal probability distribution and the central limit theorem.
A reminder is that the standard deviation is the square root of the variance.
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 = 3639, \sigma = \sqrt{145161} = 381, n = 41, s = \frac{381}{\sqrt{41}} = 59.5[/tex]
Probability that the mean of the sample would differ from the population mean by less than 126 miles
This is the pvalue of Z when X = 3639 + 126 = 3765 subtracted by the pvalue of Z when X = 3639 - 126 = 3513. So
X = 3765
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
By the Central Limit Theorem
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{3765 - 3639}{59.5}[/tex]
[tex]Z = 2.12[/tex]
[tex]Z = 2.12[/tex] has a pvalue of 0.983
X = 3513
[tex]Z = \frac{X - \mu}{s}[/tex]
[tex]Z = \frac{3513 - 3639}{59.5}[/tex]
[tex]Z = -2.12[/tex]
[tex]Z = -2.12[/tex] has a pvalue of 0.017
0.983 - 0.017 = 0.966
96.6% probability that the mean of a sample would differ from the population mean by less than 126 miles