Examine the sample data in the accompanying table. 5.9 5.3 1.6 7.4 8.6 1.2 2.1 4.0 7.3 8.4 8.9 6.7 4.5 6.3 7.6 9.7 3.5 1.1 4.3 3.3 8.4 1.6 8.2 6.5 1.1 5.0 9.4 6.4

a. Construct a stem-and-leaf plot to assess whether the data are from an approximately normal distribution.

b. Compute s for the sample data.

c. Find the values of QL and QU, then use these values and the value of s from part b to assess whether the data come from an approximately normal distribution.

d. Generate a normal probability plot for the data and use it to assess whether the data are approximately normal. Applying the Concepts—Basic