Starter:

Interpreting Pie ChartsInterpreting Pie Charts

Decide whether you agree with the following statements and give a reason

There are more pupils with mobile phones at There are more pupils with mobile phones at School A.School A.

School A (1200 pupils) School B (1000 pupils)

There are the same number of boys in both classes.There are the same number of boys in both classes.

Class 7A (24 pupils) Class 7B (32 pupils)

boys boysgirls

girls

Number of hours spent on homework last night for a class

A 1/3 of pupils spent more than 2 hours on homework last night.

2

00

1

2

3

4

Pie Charts

Be able to construct a pie chart from a collection of data, using a

protractor.

Makes of car in a school car park

Make Cavalier Ford Rover Volvo

Frequency 3 2 4 1

Construct a pie chart to show this information.

A full circle is 360o

There are a total of 3+2+4+1 = 10 cars.

So each pupil will be represented by

10

360o= 36o

Makes of car in a school car park

Make Cavalier Ford Rover Volvo

Frequency 3 2 4 1

Angle in pie chart

We use 36o to represent each car so the3 Cavaliers are represented by 3x36o = 108o

3x36o

=108o

2x36o

=72o4x36o

=144o

1x36o

=36o

Makes of car in a school car park

Make Cavalier Ford Rover Volvo

Angle 108o 72o 144o 36o

Mark the centre of the pie and draw the circle.

Draw a line from the centre to the edge

Measure the first angle needed (108o)

Draw in the line and label the section

108oCavalier

Makes of car in a school car park

Make Cavalier Ford Rover Volvo

Angle 108o 72o 144o 36o

From this line measure the next angle, draw the line and label the section.

Continue in this way

Check that the last section has the correct angle and label it.

72o

Cavalier

Ford

144oRover

36o

Volvo

108o

Why?• Why do we use 36o to represent 1 car?

• What would happen if there were 60 cars?

• What about 20 cars?

If there were 20 cars in your survey, what angle would you use to represent 4 cars? 7 cars? 12 cars?

Q1 A survey of how 30 pupils got to school

Q2 How Cameroon spent his £40 birthday money

Q3 A warden made 45 Sightings at a Wildlife park.

Construct Pie charts questions

Method Walk Cycle Car Bus

Frequency 15 5 6 4

How Games Clothes Books Cinema

Amount £6 £19 £9 £6

Animal Giraffe Wildebeest Lion Zebra

Frequency 11 19 6 9

The pie chart shows which sport 36 pupils played yesterday.

120o

80o

30o

What is the size of the missing angle?

What angle represents one pupil?

How many pupils played football?