Direct Proportion Homework

Ratio and Proportion Name ______

1. Kitchen flooring is sold at £8.00 per 1 metre length. Find the cost of:

(a) 5m (b) 50cm (c) 80cm

2. A school employs teachers in the ratio 1:20 to the number of children.

a. If the school has 600 children, how many teachers does it need? b. If the school has 15 teachers, how many children can it take?

3. The weights of two tins of fruit are in the ratio 3:5.

Find the weight of the smaller tin as a percentage of the weight of the large tin.

4. This is a list of ingredients needed to make 24 scones.

600g flour 100g dried fruit 250g butter water to mix

a. How much dried fruit is needed for 6 scones? b. How much flour would you need for 40 scones?

5. These are the ingredients needed for making 18 rock cakes.

9 ounces of flour 6 ounces of sugar 6 ounces of margarine 8 ounces of mixed dried fruit 2 large eggs

a. Justin wants to make 12 rock cakes. How much of each ingredient will he need?

b. Ali has 9 ounces of margarine, but plenty of all the other ingredients. What is the greatest number of rock cakes she can make?

6. In a class there are 16 girls and 14 boys. What is the ratio of girls to boys. Write your ratio in its simplest form.

a. What proportion of the total students are girls?

b. Write your answer as a fraction and as a percentage?

7. To make suet you need flour and fat in the ratio 3:1. If you need 160g of suet how much flour and fat do you need?

8. A 500g box of breakfast cereal costs 96p. A 300g box of breakfast cereal costs 64p. Which box represents the best value?

9. The ratio of students in a class who own a PS3, Xbox or Gamecube is 5:3:1

a. There are 27 students in the class. How many own a PS3?

10. A 300ml bottle of cola costs £2.62. A 200ml bottle costs £1.50. Which is the best value?

11. An MP3 player that can hold 1000 tracks costs £80. A different MP3 player which holds only 700 tracks costs £60. Which is the best value?

12. A painter has 2 cans of paint; each can hold 5 litres of paint. The first one is full of red paint. The second has 3 litres of yellow paint in it. He pours 2 litres of red paint into the second can and mixes it up. He then pours 2 litres of the orange paint back into the first can and mixes it up.

a. How much red paint is there now in the first can?

He again pours 2 litres of paint from the first can into the second can, mixes it up and pours 2 litres back into the first can.

b. How much red paint is now in the first can?

c. In the second can what is the ratio of yellow paint to red paint?

The painter wants to make sure that there is exactly the same amount of red paint in both cans. d. If he continues mixing the paint like this will he ever achieve this? Explain why.