1. Use the sample to find a point estimate for the mean training time of the

(a) Male runners.

(b) Female runners.

2. Find the sample standard deviation of the training times for the

(a) Male runners.

(b) Female runners.

3. Use the sample to construct a 95% confidence interval for the population mean training time of the

(a) Male runners.

(b) Female runners.

4. Interpret the results of Exercise 3.

5. Use the sample to construct a 95 % confidents interval for the population mean training time of all runners. How do your results differ from those in exercise 3?

6. A trainer wants to estimate the population mean running times for both male and female runner within 2 minutes. Determine the minimum sample size required to construct a 99% confident interval for the population mean training time

(a) Male runners. Assume the population standard deviation is 8.9 minutes.

(b) Female runners. Assume the population standard deviation is 8.4 minutes.