A major restaurant chain claims the mean waiting time for customers is no more than 9 minutes. A random sample of 35 customers was selected and the waiting time recorded. The mean waiting time was found to be 9.95 minutes with a standard deviation of 2.00 minutes. Perform the appropriate test of hypothesis.
Use this information to answer Questions 1 - 7.
1. What is the appropriate null hypothesis?
2. What is the appropriate alternative hypothesis?
3. What is the value of the test statistic?
4. What is the appropriate rejection region? (Use α = 0.05.) 5. What is the appropriate conclusion?
6. What is the p-value for this problem?
7. Find a 90% confidence interval for the true mean waiting time.
The life of a battery used in a designer dog leash is assumed to be approximately normally distributed. A random sample of 10 such batteries is selected and placed on accelerated life test yielding the following results (measured in hours):
80 73 92 82 77 75 88 76 95 105
The manufacturer of the battery claims the mean battery life is 75 hours. Use this information to answer Questions 8 - 13.
8. What is the appropriate null hypothesis?
9. What is the appropriate alternative hypothesis?
10. What is the appropriate test to use for this problem?
(a) z-test (b) t-test (c) F-test (d) Binomial Test
11. What is the value of the test statistic?
12. What is the p-value for this problem?
13. Based on the p-value, what is the appropriate conclusion?