SOLUTION: 1. The manager of a driving school claims that the mean time taken to learn how to drive a car is 8 hours or less for all new drivers. A sample of 16 new drivers showed that the me

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Question 286706: 1. The manager of a driving school claims that the mean time taken to learn how to drive a car is 8 hours or less for all new drivers. A sample of 16 new drivers showed that the mean time taken by them to learn how to drive the car is 9.5 hours with a standard deviation of 1.5 hours. Test the manager�s claim at the 1% significance level.
a. Select the null and alternate hypothesis.
b. Determine the critical values of the test statistic.

c. What equation/formula would you use?
d. Using the statistical calculator or manual calculation what is the observed statistic and what is your decision regarding the null hypothesis. Provide a one sentence answer.

Answer by stanbon(75887) (Show Source):
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1. The manager of a driving school claims that the mean time taken to learn how to drive a car is 8 hours or less for all new drivers. A sample of 16 new drivers showed that the mean time taken by them to learn how to drive the car is 9.5 hours with a standard deviation of 1.5 hours. Test the manager�s claim at the 1% significance level.
a. Select the null and alternate hypothesis.
Ho: u <= 8 hrs
Ha: u >= 8 hrs
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b. Determine the critical values of the test statistic.
invT(0.99 with df = 15) = 2.6042
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c. What equation/formula would you use?
t(9.5) = (9.5-8)/[1.5/sqrt(16)] = 4
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d. Using the statistical calculator or manual calculation what is the observed statistic and what is your decision regarding the null hypothesis. Provide a one sentence answer.
Conclusion: Since the test statistic is in the reject interval,
reject Ho.
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Cheers,
Stan H.
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