Ratio and Proportion

The cost of a computer processor is directly proportional to its speed.

A 4GHz processor costs £400.

Find the cost of a 6GHz processor.

At a steady speed, a train uses 15 litres of petrol to travel 50 km.

At the same speed, what distance could be travelled using 18 litres of petrol?

Leo makes a cake by mixing flour, eggs and sugar in the ratio 5 : 3 : 2.

If he uses 120 g of sugar, what weight of eggs will he need?

If it costs £55 to buy 11 cushions, how much will it cost to buy 19?

Andrew is paid £250 a week.

Each week, he

shares his pay with his sister in the ratio 3 : 2

saves 12% of his share.

How many weeks will it take Andrew to save £360?

Divide £720 in the ratio 5 : 1

• 12:60

• 576:144

• 120:600

• 600:120

Some money is shared in the ratio 7 : 13

What percentage of this money is the greater share?

Nikhil, Davina and Sid share a tin of celebrations amongst themselves in the ratio of 8:12:20 respectively.

Given that Davina gets 48 sweets, calculate the total number of sweets that were in the tin.

Sarah has £135

Gemma has £70

Beth has £35

Sarah gives some money to Gemma and Beth.

The ratio of the amount of money Sarah, Gemma and Beth have now is 3:2:1

How much money did Sarah give to Gemma?

There are 60 children in a club.
In the club, the ratio of the number of girls to the number of boys is 3:1

 $\frac{3}{5}$  of the girls play a musical instrument.

 $\frac{4}{5}$   of the boys play a musical instrument.

What fraction of the 60 children play a musical instrument?