Page 413 - Math Smart - 7

Part 1: Draw a pie chart
Use a pie chart to represent the data in the table on the most common eye colour
of pupils in a class.

Eye colour Grey Green Brown Blue

Frequency 12 7 13 4

Solution
First, work out the data.

The fraction^ shows that Add a column to find

12 of the 36 pupils surveyed each sector angle. For each sector, divide the frequency
by the total and multiply by 360°.
This answer is the size of the angle of
Eye colour Frequ^icy Sector angle (°) the sector that represents the pupils
with grey eyes.
Grey 50° = 120° '

Green 7 ^ X 360° = 70°
Think and Share
Brown 13 360° = 130°
1
multiply
Find the Blue 4 ^ X 360° = 40°
sum of the
Total ^"*^36 360°
frequencies.

Then, draw your pie chart. Eye colour

Brown
m

Green

Use a compass to draw your Use a protractor to measure the angle Colour and label your pie chart,
pie chart. of each sector. Pencil in the sectors.

Part 2: Interpret a pie chart
Refer to the pie chart in Part 1.

Which eye colour was the most common?
Which eye colour was the least common?
What percentage of the pupils surveyed had blue eyes?
I
*
^ Challenge Of the 36 pupils surveyed, how many had green eyes?
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