Pie charts

Pie charts

Learning objectives

• To understand pie charts

• How to calculate the degrees of each segment

• How to write it as a fraction

Before we get into the math

lets look at some basic pie charts and retrieve information

Multiple Choice

Which animal is the most popular?

• dog

• parrot

• hamster

Multiple Choice

Which animal has

 $\frac{1}{4}$  of the pie chart. 

• hamster

• dog

• cat

Lets step up!

Multiple Choice

The pie chart represents 40 children. How many children chose summer?

• 10

• 20

• 5

Multiple Choice

How many children chose spring?

• 10

• 40

• 20

Multiple Choice

How many children chose spring?

• 10

• 40

• 20

How do we calculate the proportion of the pie that each bit of data should take?

• We use degrees and draw angles to illustrate the part of the pie each piece of data should have.

• We already know that a full turn around a point is 360 $\degree$  

Here is a table

It shows us how 60 people voted in a favourite takeaway poll.

How do we put this into an accurate pie chart?

What do we know?

• We know that a full turn is  $360\degree$  

• We know that 60 people answered the survey

• Can we use this information to calculate how many degrees one person would equal on a pie chart?

Think about it..

• Each person is equal

•  $\frac{360}{60}=6$  

  We can share the amount of degrees equally between the 60 people.

• Each person is represented by  $6\degree$  on the pie chart!

Now we can work out how many degrees are in each group.

We do this by multiplying the number of people who are in the group by the number of degrees each person is worth.

Multiple Choice

Quick fire division
 $360\div90=$   

• 3

• 4

• 5

Multiple Choice

How many degrees in a full turn?

• $180\degree$

• $270\degree$

• 360 $\degree$

Multiple Choice

 $360\div40=$  

• 8

• 9

• 10

The best thing to master pie charts is:

• Practice

• Practice

• and practice!

• Lets have a go!

Multiple Choice

How many degrees is the spring angle?

• $90\degree$

• $45\degree$

• 60 $\degree$

Multiple Choice

90 students answer a survey, How many degrees does each student represent?

• $3\degree$

• 4 $\degree$

• 6 $\degree$

Multiple Choice

A PIE Chart is created using

• Cherries

• Apples

• Data

• Cars

Multiple Choice

A darts player hits his target 40% of the time. Which pie chart represents his hits and misses?

Multiple Choice

How many birds are represented by the green sector?

• 5

• 20

• 9

• 13

Multiple Choice

Which Continent is home to 36% of the wild cats?

• Asia

• Africa

• North America

• South America

Multiple Choice

Students were surveyed about their favorite sports to play in phys.ed. The results are represented in this circle graph. If 48 students were surveyed, how many chose soccer?

• 10
• 12
• 15
• 14

Phew! Done!

Don't forget! Hegarty, Q & A, RYG!