Hypothesis Testing

3. Metro Bank claims that the mean wait time for a teller during peak hours is less than 4 minutes. A random sample of 20 wait times has a mean of 2.6 minutes with a sample standard deviation of 2.1 minutes. Assume the distribution is normally distributed.
 

a. Use the critical t0 value method to test Metro Bank’s claim that the mean wait time is less than 4 minutes. Test the claim at the level of significance a = 0.05.
 

(References: example 1 through 5 pages 397 – 401, end of section exercises 23 – 28 pages 404 – 405) (6 points)
 

1. H0:
Ha:
2. a = 0.05
3. Test statistic(t):
4. Critical t0:
5. Rejection Region:
6. Decision:
7. Interpretation:

 

b. Use the critical t0 value method to test Metro Bank’s claim that the mean wait time is less than 4 minutes. Test the claim at the level of significance a = 0.01
 

(References: example 1 through 5 pages 397 – 401, end of section exercises 23 – 28 pages 404 – 405) (6 points)
 

1. H0:
Ha:
2. a = 0.01
3. Test statistic(t):
4. Critical t0:
5. Rejection Region:
6. Decision:
7. Interpretation:

Section 7.4: Hypothesis Testing for Proportions.
 

4. In a recent poll, it was found that 43% of registered U.S. voters would vote for the incumbent president. If 100 registered voters were sampled randomly, it was found that 35% would vote of the incumbent. Test the claim that the actual proportion is 43%. Use a = 0.01. (Round that to 2 decimal places.)
 

(References: examples 1 through 3 pages 408 – 410, end of section exercises 9 – 14 pages 411 – 412) (8 points)
 1. H0:
Ha:
2. a =0.01
3. Test statistic (z):
4. P-value or critical z0:
5. Rejection Region:
6. Decision: