GCSE Mathematics

Targeting Grade C

Number Unit 6 Ratio

Can you…

•Find parts of a ratio •Share an amount in a ratio Try a test If not you need TOP: Review simple ratios Practice 1: Cancelling ratios and finding missing parts Practice 2: given ratio Sharing an amount in a TAIL

TOP: Solve these simple ratio questions (1) Bob has 7 pens and Sarah has 14 pens. Write this as a ratio in its simplest terms.

(2) Joanne has 12 kittens and Louie has 3 kittens. Write this as a ratio in its simplest terms.

(3) Write these ratios in their lowest terms: (a) 5 : 35 (b) 28 : 14 (c) 18 : 36 : 42 (d) 40cm : 1m Lesson

Practice 1:

(1) (2) (3) (4) (5) 15 : 20 35 : 40 10 : 35 8 : 24 120 : 150 Cancel the following ratios into their lowest terms: Using the given ratio, find the missing part in the second ratio in each question.

(6) 3 : 4 (7) 3 : 7 (8) z : 5 x : 12 12 : y 15 : 20 (9) 12 : 15 a : 3 (10) 8 : 4 32 : b (11) 2 : 5 9 : c Lesson

Practice 2:

(1) Solve the following ratio problems: Malika's father won £128. He shared the £128 between his three children in the ratio 6:3:1. Malika was given the biggest share. Work out how much money Malika received.

(2) Bill gave his three daughters a total of £32.40. The money was shared in the ratio 4:3:2. Jane had the largest share. Work out how much money Bill gave to Jane. (3) Georgina split £26 between her children Fred and Sue in the ratio 3:1. How much did each child get?

(4) Catherine bought 150 cakes to be split between her three maths classes 11A, 11B & 11C. They were split in the ratio 5:6:4. Work out how many cakes each group got.

Lesson

TAIL (1) In a recipe that makes 8 cakes, I use 200g flour, 200g butter, 100g sugar and four eggs. How much of each ingredient will be needed for (a) 16 cakes (b) 12 cakes (c) 36 cakes?

(1) (a) 400, 400, 200, 8 (b) 300, 300, 150, 6 (c) 900, 900, 450, 18 (2) Bronze is made from copper and tin. The ratio of the weight of copper to the weight of tin is 3:1.

(a) (b) Work out the weight of copper and the weight of tin in 120 grams of bronze.

(2) (a) 36  3 = 12, 12 + 36 = 48 What weight of bronze contains 36 grams of copper?  4 = 30 30  3 = 90 (3) Kylie went to Paris and changed £200 into euros. The exchange rate was £1 = 9.6 euros.

30  1 = 30 (a) Work out the number of euros Kylie got.

(3) (a) 200  9.6 = 1920€ When Kylie came home she bought back 25 euros. The exchange rate was £1 = 10 euros.

(b) 25  10 = £2.50

(b) Work out how much she had got in pounds.

Are you ready for the answers ?

Lesson