How_To_Be_Good_At_Math

70 NUMBERS •^ RATIO

Simplifying ratios

As with fractions, we always simplify ratios when we can. We do this by

dividing both numbers in the ratio by the same number.

Ratio

Ratio is the word we use when we compare two

numbers or amounts, to show how much bigger

or smaller one is than the other.

Three strawberry cones Four chocolate cones

40 g puffed rice

cereal

For every 40 g of cereal

we use, we need 50 g of

chocolate. So the ratio of cereal

to chocolate in the recipe is 40:50.

Let’s look at these seven

ice cream cones. Three are

strawberry and four are chocolate,

so we say that the ratio of strawberry

to chocolate cones is 3 to 4.

In this recipe, 40 g of puffed

rice cereal, plus 50 g of

melted chocolate, makes six

mini treats.

The symbol for the ratio between

two amounts is two dots on top

of each other, so we write the ratio of

strawberry to chocolate cones as 3:4.

To simplify the ratio, we

divide both numbers by

10 to make a ratio of cereal to

chocolate of 4:5.

Simplify the ratio

by dividing both

numbers by 10

40:50

4:5

÷ 1 0 ÷ 1 0

RATIO OF STRAWBERRY TO CHOCOLATE CONES IS

40 : 50 =

3 : 4

50 g chocolate

4 : 5

Ratio tells us how much we

have of one amount

compared to another amount.

070-071_Ratio_Proportion.indd 70 29/02/2016 14:10