In KS2 Maths children will come to understand how to use ratio to represent the relation between numbers. In Year Six children should be confident when converting ratios into fractions, and vice versa.

Ratio is the relation between two numbers or quantities. It is useful for showing the number of times one value contains or is contained within the other. For instance in the ratio 1:3, if 1 is sand and 3 is water, you would need three times the amount of water in relation to sand. Ratios are excellent tools which help us to visualise how different numbers of things compare to one another. They are also very similar to fractions. The ratios 1:3 and 2:3 can also be represented by the fractions ^{1}⁄_{3} and ^{2}⁄_{3}

How well do you understand ratios? Test your knowledge by playing the following quiz and see if you can get a ratio of 10:0 right to wrong answers!

1.

A biscuit recipe needs 250g flour, 150g of sugar and 150g of butter to make 6 biscuits. How much butter is needed to make 18 biscuits?

150g

300g

400g

450g

18 is 3 x 6 so we multiply 150g by 3

2.

In every 10 tiles there are 2 red tiles. What is the proportion of red tiles?

3.

Jo mixes 400ml of orange juice to every 200ml of pineapple juice to make a fruit cocktail. How much orange juice will she need to make 900ml of fruit cocktail?

200ml

400ml

600ml

800ml

There is 400ml in every 600ml. 900ml = 1.5 x 600ml. So multiply 400ml by 1.5

4.

For every 4 litres of petrol a car can travel 80km. How much petrol is required for a journey of 100km?

5 litres

8 litres

10 litres

12 litres

If 4 litres can travel 80km we divide by 4 to find 1 litre will travel 20km. So 5 litres will travel 100km

5.

There are 2 white cubes for every 1 blue cube. What proportion are blue cubes to white cubes?

6.

In every 12 tiles the proportion of blue tiles is ^{3}⁄_{4}. How many blue tiles in every 12?

3

6

8

9

7.

The proportion of brick houses in every 20 is ^{3}⁄_{10}. How many brick houses in a street of 100 houses?

6

10

30

50

8.

If there is a 10:1 ratio between black squares and white squares which number represents white squares?

1

2

5

10

The 10 represents black and the 1 represents white because black was mentioned first and white second

9.

In a box of chocolates there are 4 milk chocolates to 3 dark chocolates. How many dark chocolates in a box of 49 chocolates?

7

21

28

30

There are 3 dark chocolates in every 7. There are seven 7s in 49 so we multiply 3 by 7

10.

In a grid of 10 squares 4 are white and the rest are blue. What is the ratio of white to blue?

1:2

2:4

4:6

5:6

10 - 4 = 6 so there are 6 blue squares for every 4 white squares