A circle graph shows shares of a whole rather than amounts, so reading one always takes a second step. These free printable worksheets give the chart and the total, and ask how many the shaded share actually comes to.
If they get stuck
The answer key prints on a separate page.
Twenty-five percent of the circle is a quarter of it, and a quarter of two hundred is fifty. The chart says the fraction and the caption says the total, and the question cannot be answered from either alone — which is the one thing a pie chart does that a bar graph does not, and the reason it is worth its own sheet.
The slices are drawn to scale, so the picture can be used as a check. If a slice looks like about a third and the answer is not about a third of the total, something has gone wrong in the arithmetic and it will be visible before the key is opened.
One question from a sheet like this one, worked a step at a time — with a sentence saying what just happened and why.
Circle graphs, step by step