How_To_Be_Good_At_Math

292 STATISTICS •^ PIE CHARTS

Let’s look at this pie chart. It

shows the types of film that

a group of school children said

they most liked to watch.

We can compare the film

types just by looking at the

chart. It’s clear that comedies

are most popular and science

fiction films are liked the least.

Even though there are no

numbers on the chart, we

can still understand it. The bigger

the sector, the more children

chose that type of film.

Pie charts

A pie chart presents information visually. It’s a diagram that

shows data as “slices”, or sectors, of a circle. Pie charts are a

good way of comparing the relative sizes of groups of data.

Labelling sectors

There are two other ways of

labelling pie charts: using a

key or using labels.

Action

Science

fiction

Comedy

Key

We use the colours in the

key to find out what type of film

each sector represents.

Labels

We can also write our

labels beside the chart or write

them on the chart like here.

Thrillers are

less popular than

action movies

Largest

sector

The labels on this

chart show what each

sector represents

Comedies

are most

popular

Thriller

Thriller

Science

fiction

Comedy

Action

Science fiction

Thriller

Comedy

Action

Favourite types of movie

The bigger the slice,

the more data it

represents.

KEY

292_293_Pie_charts.indd 292 29/02/2016 18:06