pie chartsfor erin

Part 1:Pie charts with FRACTIONS

To understand a pie chart, you need to find out 2 pieces of information:

1) what is the total number?E.g. 40 children in total

2) what are the fractions? E.g. ¼ of each

There are 40 children in the class.

Black hairBrown hairBlond hairRed hair

1/4

How many children in total?

Black hairBrown hairBlond hairRed hair

1/4

How many have black hair?

There are 40 children in the class.

Black hairBrown hairBlond hairRed hair

1/4

What is ¼ of 40?

Children with black hair are¼ of the total (40)

There are 40 children in the class.

Black hairBrown hairBlond hairRed hair

1/4

10 children with black hair

There are 40 children in the class.

Black hairBrown hairBlond hairRed hair

10

10

10

10

There are 40 children in the class.

Now do the exercises in yourSchofield & Sims ‘Graphs, Charts and Data’ bookPage 25

Part 2:Pie charts with PERCENTAGES

Treat PERCENTAGES the same way as fractions:

To understand a pie chart, you need to find out 2 pieces of information:

1) what is the total number?E.g. 40 children in total

2) what are the fractions? You need to convert the percentages to fractions!

The fraction will be /100.

There are 40 children in the class.

Black hairBrown hairBlond hairRed hair

25%

How many children in total?

Black hairBrown hairBlond hairRed hair

25%

How many have black hair?

There are 40 children in the class.

Black hairBrown hairBlond hairRed hair

25%

What is the fraction?

Children with black hair are25% of the total (40)

There are 40 children in the class.

25% = 1/4

Black hairBrown hairBlond hairRed hair

25%

¼ of 40 = ?

Children with black hair are25% of the total (40)

There are 40 children in the class.

Black hairBrown hairBlond hairRed hair

1/4

10 children with black hair

There are 40 children in the class.

Black hairBrown hairBlond hairRed hair

10

10

10

10

There are 40 children in the class.

Boys

Girls

60 children in total

60%40%

How many children in total?

Boys

Girls

60 children in total

60%40%

How many are boys?

Boys

Girls

60 children in total

60%40%

What is the fraction?

Boys

Girls

60 children in total

60%40%

40% = 40/100 = 4/10

Boys

Girls

60 children in total

60%40%

4/10 of 60 = ?

Part 3:Pie charts with DEGREES

Treat PERCENTAGES the same way as fractions:

To understand a pie chart, you need to find out 2 pieces of information:

1) what is the total number?E.g. 40 children in total

2) what are the fractions? You need to convert the degrees to fractions!

The fraction will be /360.

vanillachocolatemango18

0°

90°

60 children in a class

?

vanillachocolatemango18

0°

90°

60 children in a class

?

What is the fraction?

vanillachocolatemango18

0°

90°

60 children in a class

?

180°/360°

What is the fraction?

vanillachocolatemango18

0°

90°

60 children in a class

?

180°/360° = 18/36 = 1/2

vanillachocolatemango18

0°

90°

90°

60 children in a class

As always, to understand such a pie chart, you need to find out 2 pieces of information:

1) what is the total number?E.g. 40 children in total

2) what are the fractions create an equivalent fraction!! E.g. 90° = 90/360 = 1/4

Examples:

180°60°90°

= 180/360 = 1/2= 60/360 = 1/6= 90/360 = 1/4

120°= 120/360 = 1/3

vanillachocolatemango

180°

360 ° = 40 children

vanillachocolatemango

180°360°

360 ° = 40 children

vanillachocolatemango

180360

360 ° = 40 children

12

=

vanillachocolatemango

180360

360 ° = 40 children

12

=

vanillachocolatemango18

0°

360 ° = 40 children

½ of the total (40)= 20 children

vanillachocolatemango18

0°

90°

90°

360 ° = 40 children

½ of the total (40)= 20 children

¼ of the total (40)= 10 children