Pie charts
Answers are for parents and teachers.
1
Twenty-four pupils choose a fruit: apple 6, banana 10, orange 8. Find the three angles of a pie chart.
One pupil is 360° ÷ 24 = 15°. Apple 90°, banana 150°, orange 120°. Check: 90 + 150 + 120 = 360.
2
Find the angles for the percents 35%, 45% and 20%.
35 × 3.6 = 126°, 45 × 3.6 = 162°, 20 × 3.6 = 72°. Check: 126 + 162 + 72 = 360.
3
A pie chart is for 80 pupils. The swimming sector has the angle 45°. How many pupils swim?
45/360 × 80 = 10 pupils.
4
What percent of the circle is a sector of 54°?
54/360 × 100 = 15%.
5
Name the best graph for (a) how a 600 LE budget is shared between food, rent and transport, and (b) the heights of 30 pupils in intervals.
(a) a pie chart, because it shares one whole. (b) a histogram, because the data are in intervals.