2.34 In Chapter 1, we described graphically using a frequency distribution table and a histogram the time (in seconds) for a random sample of n = 110 employees to complete a particular task. Describe the data numerically based on the frequency distribution given in Table 1.7. The data is stored in the data file Completion Times.

a. Compute the mean using Equation 2.21.

b. Compute the variance using Equation 2.22.

c. Compare your answers to the mean and variance calculated in Exercise 2.23.