1. (Hypothesis test for small sample sizes)
T-Test
(Hypothesis test for small sample sizes)

2. Find the critical value for
Left tail, n = 15

3. Find the critical value for
Right tailed ; n = 10

4. Find the critical value for
Two-tailed, n = 28

5. Assumptions: SRS (Simple Random Sample)
 The population is normally or approximately normally distributed
Population Standard deviation is unknown and n < 30

6. The Standardized test statistic t is:

7. Example:
The American Automobile Association claims that the mean nightly lodging rate for a family of four traveling on vacation in California is at least $136. A random sample of eleven such families has a mean nightly lodging rate of $126 with a standard deviation of $12. Is there enough evidence to reject the claim at Assume the population is normally distributed.

8. a)      Write the null and alternative hypothesis mathematically and identify the claim:
(claim) :

9. Find the critical values and identify the rejection region

10. Find the standardized test statistic=

11. Conclusion
Decide whether to reject or fail to reject the null hypothesis. Then interpret the decision in the context of the original claim.
At the 10% level, reject the null hypothesis. Evidence does not supports the claim that the mean daily meal cost is greater than or equal to $136.

12. Now do Practice 7.3