Area and proportion

An important property of histograms is that the area of each class's rectangle is proportional to the number of values in the class. Similarly, the area above any collection of classes gives the proportion of values in these classes.

In the first exercise, the number of values in each histogram class is shown, making it easier to calculate the required proportion exactly (using the template provided).

Using areas

The following exercise is similar, but the numbers of values in the classes are not shown, so the proportion of the total area corresponding to the given interval must be estimated 'by eye'.

Again, estimate the proportion of values in the question.

Repeat with a few other questions.