Histograms for grouped data

Here are the shopping times (in minutes) for a sample of 18

shoppers at a particular grocery store:

26,23,44,41,38,35,31,28,25,22,31,31,27,27,24,24,21,21

Draw the histogram for these data using an initial class boundary of 20.5

, an ending class boundary of 45.5

, and 5

classes of equal width. Note that you can add or remove classes from the figure. Label each class with its endpoints.