Name _ Solutions Version 3__
Fall ‘10
Computer Assignment #4
Math 159
Do ALL calculations (including rounding) in Excel
1. (14 pts) For all parts of this problem, use the sample data given in the Excel
document, and use α = 0.05. Assume the population distribution is normal.
a. Find the following statistics for your sample. Round your answer for s to five decimal
places.
n = 43
s = 24.38609
b. You want to test the claim that the population standard deviation is at most 21.
Fill in the hypotheses here:
H0: σ ≤ 21
H1: σ > 21
Calculate the test statistic for this test. Round your answer to five decimal places.
Test statistic is 56.63633
Use an appropriate command in Excel to find the p-value for this hypothesis test.
Round your answer to four decimal places.
p-value = 0.0652 > α
Check the initial conclusion:
❑ Reject H0
❑ Fail to Reject H0
Conclusion as a complete sentence:
There is not enough evidence to reject the claim that the population
standard deviation is at most 21.
2. (12 pts) For all parts of this problem, use the independent samples given in the Excel
document, and use α = 0.05. Assume the population distributions are normal.
H0: µ1 – µ 2 = 0
H1: µ1 – µ 2 ≠ 0
a. Use the appropriate TTEST command in Excel to find the p-value for this hypothesis
test. Round your€answer to four decimal places.
p-value = 0.0024 < α
€
Check the initial conclusion:
❑ Reject H0
❑ Fail to Reject H0
b. Use the appropriate Data Analysis command in Excel to find the test statistic and the
critical value for this hypothesis test. Round your answers to four decimal places.
Make sure your answer is complete.
ttest = 3.2051
Check the initial conclusion:
tcrit = ± 2.0096
❑ Reject H0
❑ Fail to Reject H0
3. (12 pts) For all parts of this problem, use the matched pairs samples given in the Excel
document, and use α = 0.05. Assume the distribution of differences is normal.
H0: µ1 – µ 2 ≥ 0
H1: µ1 – µ 2 < 0
a. Use the appropriate TTEST command in Excel to find the p-value for this hypothesis
test. Round your€answer to four decimal places.
p-value = 0.0961 > α
€
Check the initial conclusion:
❑ Reject H0
❑ Fail to Reject H0
b. Use the appropriate Data Analysis command in Excel to find the test statistic and the
critical value for this hypothesis test. Round your answers to four decimal places.
Make sure your answer is complete.
ttest = –1.3498
tcrit = –1.7247
Check the initial conclusion:
❑ Reject H0
❑ Fail to Reject H0
4. (12 pts) For all parts of this problem, use the independent samples given in the Excel
document, and use α = 0.05. Assume the population distributions are normal.
H0: σ 1 ≤ σ 2
H1: σ 1 > σ 2
a. Use the FTEST command in Excel to find the p-value for this hypothesis test. Round
€ decimal places.
your answer to four
p-value = 0.0225 < α
€
Check the initial conclusion:
❑ Reject H0
❑ Fail to Reject H0
b. Use the appropriate Data Analysis command in Excel to find the test statistic and the
critical value for this hypothesis test. Round your answers to four decimal places.
Ftest = 1.9262
Check the initial conclusion:
Fcrit = 1.7104
❑ Reject H0
❑ Fail to Reject H0