Question 1010417: 1.A 95% confidence interval for the mean of a normal population is found to be 17.6 < µ < 23.6. What is the margin of error?
A. 2.0
B. 2.7
C. 3.0
D. 4.0
2.A 95% confidence interval for the mean of a normal population is found to be 13.2 < µ < 22.4. What is the margin of error?
A. 4.6
B. 4.4
C. 4.2
D. 5.6
3.One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent.
The critical value of X2 for a 2 x 2 table using a 0.05 significance level is 3.841. If the value of the X2 statistic is 4.613, state your conclusion about the relationship between gender and colorblindness.
A.
Reject H0. There is not sufficient evidence to support the claim that gender and colorblindness are related.
B.
Reject H0. There is sufficient evidence to support the claim that gender and colorblindness are related.
C.
Do not Reject H0. There is sufficient evidence to support the claim that gender and colorblindness are related.
D.
Do not Reject H0. There is not sufficient evidence to support the claim that gender and colorblindness are related.
4.A golfer wished to find a ball that would travel more than 160 yards when hit with his 7-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 8 times at the required speed.
Data from this test resulted in a sample mean of 163.2 yards with a sample standard deviation of 5.8 yards. Assuming normality, carry out a hypothesis test at the 0.05 significance level to determine whether the ball meets the golfer’s requirements. Use the partial t-table below to solve this problem.
Area in one tail
0.025 0.05
Area in two tails
Degrees of
Freedom
n - 1 0.05 0.10
6 2.447 1.943
7 2.365 1.895
8 2.306 1.860
9 2.262 1.833
A.
Do not reject the null hypothesis. The data do not provide sufficient
evidence that the average distance is greater than 160 yards.
B. Reject the null hypothesis. The data does provide sufficient evidence that the average distance is greater than 160 yards.
C. t= 1.2334; Critical value = 1.992
D. Insufficient information to answer this question
5.Which of the following statements is true?
A. The t distribution cannot be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population.
B. The t distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population.
C. The p distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population.
D. The p distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! 1.A 95% confidence interval for the mean of a normal population is found to be 17.6 < µ < 23.6. What is the margin of error?
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Every CI is 2*ME wide.
In your case:: 2*ME = (23.6-14.6) = 9
So ME = 4.5
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2.A 95% confidence interval for the mean of a normal population is found to be 13.2 < µ < 22.4. What is the margin of error?
2*ME = (22.4-13.2) = 9.2
ME = 4.6
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3.One hundred people are selected at random and tested for colorblindness to determine whether gender and colorblindness are independent.
The critical value of X2 for a 2 x 2 table using a 0.05 significance level is 3.841. If the value of the X2 statistic is 4.613, state your conclusion about the relationship between gender and colorblindness.
---
Since the test stat is greater than the critical value
we reject Ho. Therefore the factors are related.
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4.A golfer wished to find a ball that would travel more than 160 yards when hit with his 7-iron with a club speed of 90 miles per hour. He had a golf equipment lab test a low compression ball by having a robot swing his club 8 times at the required speed.
Data from this test resulted in a sample mean of 163.2 yards with a sample standard deviation of 5.8 yards. Assuming normality, carry out a hypothesis test at the 0.05 significance level to determine whether the ball meets the golfer’s requirements.
Test Statistic::
(t(163.2) = (163.2-160)/(5.8/sqrt(8)) = 1.56
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Use the partial t-table below to solve this problem.
Area in one tail
0.025 0.05
Area in two tails
Degrees of
Freedom
n - 1 0.05 0.10
6 2.447 1.943
7 2.365 1.895
8 2.306 1.860
9 2.262 1.833
---
Ho: u <= 160
Ha: u > 160 (claim)
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Using n-1 = 7 with critical values 2.365 and 1.895
we fail to reject Ho that u <= 160
A.
Do not reject the null hypothesis. The data do not provide sufficient
evidence that the average distance is greater than 160 yards.
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5.Which of the following statements is true?
A. The t distribution cannot be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population.
B. The t distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population.
C. The p distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population.
D. The p distribution can be used when finding a confidence interval for the population mean with a small sample whenever the sample comes from a symmetric population.
Ans: I'll leave this one to you. Check your textbook.
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Cheers,
Stan H.
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