A Pie Chart shows data as sectors of a circle. A pie chart is built from a table of data.
Building a pie chart consists of these steps:
• Add the frequencies to obtain a total;
• Divide 360º by the total (to get the number of degrees for one item);
• Multiply each frequency by this number;
• Plot the pie chart using these values;
• Label the pie chart and provide a title
1. A school is taking 120 students on a trip. The students come from several year groups. Plot a pie chart to represent the data.
Add frequencies for total = 120.
Each student is worth 360 ÷ 120 = 3º
Multiply each frequency by 3º
|Year 7||21||3 x 21 = 63|
|Year 8||27||3 x 27 = 81|
|Year 9||29||3 x 29 = 87|
|Year 10||32||3 x 32 = 96|
|Year 11||11||3 x 11 = 33|
Plot the chart, adding a title and labels
2. The pie chart below shows the type of cars sold by a car showroom over one month. 18 5-door cars were sold. How many SUVs were sold?
18 five-door cars = 90º
1 car = 90 ÷ 18 = 5º for each car
SUVs = 130º ÷ 5 = 26 cars