Question

Interpreting a Histogram. In Exercises 5–8, answer the questions by referring to the following Minitab-generated histogram, which depicts the weights (grams) of all quarters listed in Data Set 29 “Coin Weights” in Appendix B. (Grams are actually units of mass and the values shown on the horizontal scale are rounded.)

Gap What is a reasonable explanation for the gap between the quarters with weights between 5.5 grams and 5.8 grams and the group of quarters with weights between 6.0 grams and 6.4 grams? (Hint: Refer to the columns of quarters in Data Set 29 “Coin Weights” in Appendix B.)

Short answer

The difference in the weights of the quarters can be due to a change in the material used for making the coins after the year 1964.

Step-by-step solution

Given information

A histogram is plotted for the weights of a set of quarters.

Interpret the values of the histogram

There is a difference in the weights of quarters.

The bars on the left side of the histogram represent weights of quarters between 5.5 grams and 5.8 grams, whereas the bars on the right side of the histogram represent weights of quarters between 6.0 grams and 6.4 grams.

This gap could be because the quarters with weights between 6.0grams and 6.4 grams were made before 1964 with a heavyweight material.

Over the years, the material with which the coins were made had changed to a lighter material, and the quarters made after 1964 had weights between 5.0 grams and 5.5 grams.