Simplify the following Ratios 18 36 72 1

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Simplify the following Ratios • 18 : 36 : 72 1: 2 : 4

Simplify the following Ratios • 18 : 36 : 72 1: 2 : 4 • 350 g : 7 kg 1 : 20 • 0. 12 : 2. 4 : 6 1 : 20 : 50 Note that: When the units are the same. . they drop. It is understood that when a ratio has no units then each part is of the same units!

Finding an unknown quantity in a given Rat (a) A fruit drink is made

Finding an unknown quantity in a given Rat (a) A fruit drink is made by mixing lemon squash with water in the ratio 4: 5. How much water needs to be added to 28 cl of lemon squash to make the drink? SQUASH : WATER 28 ÷ 4 x 7 : 5 4 ? 28 cl : 35 cl x 7 Therefore, 35 cl of water needs to be added to make the drink. (b) To make Squirrel Grey paint, you need to mix Snow White and Beetle Black together in a ratio of 3: 2. How much Snow White will you need if you’re using 18 litres of Beetle Black? WHITE : BLACK x 9 : 2 3 : 18 litres 27 litres ? x 9 18 ÷ 2 Therefore, 27 litres of Snow White needs to be mixed to make Squirrel

Finding an unknown quantity in a given Ratio The ratio of female to male

Finding an unknown quantity in a given Ratio The ratio of female to male members of a tennis club is 3 : 8. The total number of females in the club is 51. How many members are male? FEMALE : MALE 51 ÷ 3 x 17 3 51 : 8 : 136 ? x 17 Therefore, 136 members of the tennis club are male.

Ques 1 In a room, the ratio of men to women is 4: 1.

Ques 1 In a room, the ratio of men to women is 4: 1. If there are 20 men, how many women are there? 5 women TRUE – STAND UP STAY PUT FALSE –

Ques 2 In a shop the ratio of oranges to apples is 2: 5.

Ques 2 In a shop the ratio of oranges to apples is 2: 5. If there are 60 apples, how many oranges are there? 84 oranges TRUE – STAND UP STAY PUT FALSE –

Ques 3 In a train the ratio of adults to children is 7: 2.

Ques 3 In a train the ratio of adults to children is 7: 2. If there are 126 adults, how many children are there? 36 children TRUE – STAND UP STAY PUT FALSE –

Ques 4 In a room, the ratio of men to women is 7: 2.

Ques 4 In a room, the ratio of men to women is 7: 2. If there are 42 men, how many women are there? 12 women TRUE – STAND UP STAY PUT FALSE –

Ques 5 In a box, the ratio of nails to screws is 8: 4.

Ques 5 In a box, the ratio of nails to screws is 8: 4. If there are 16 screws, how many nails are there? 10 nails TRUE – STAND UP STAY PUT FALSE –

Ques 6 An alloy consists of copper, zinc and tin in the ratios 2:

Ques 6 An alloy consists of copper, zinc and tin in the ratios 2: 3: 5. If there is 20 g of copper, there are 30 g of zinc and 50 g of tin. TRUE – STAND UP STAY PUT FALSE –

Ques 7 A ‘good’ children’s book is supposed to have pictures and text in

Ques 7 A ‘good’ children’s book is supposed to have pictures and text in the ratio 17 : 8. In a book I have just looked at, the pictures occupy 34 pages. How many pages of text should this book have to be a ‘good’children’s book? 16 pages TRUE – STAND UP FALSE – STAY PUT

Group of 4 : Numbered Heads 1. Olive is making cakes, she needs sugar

Group of 4 : Numbered Heads 1. Olive is making cakes, she needs sugar and flour in the ratio 1: 4. If she has 20 g of sugar, how much flour does she need? 2. Tim is mixing red and white paint in the ratio 2: 3. He has 10 litres of red, how much white does he need? 3. A Cocktail needs pineapple to apple in the ratio 3: 7. How many bottles of apple juice should go with 9 bottles of pineapple juice? 4. Some peanuts, cashew nuts and walnuts are mixed in the ratio 1: 3: 5. How much of the other nuts are needed if 12 peanuts are used?

L. O. To be able to find an unknown quantity in a given ratio

L. O. To be able to find an unknown quantity in a given ratio • It is the opposite of simplifying (so don’t simplify again – you must find the unknown quantity!) • Write the ratio in words in the correct order • Write the simplified ratio given under the words • Write the quantity that you know underneath the correct word & number • Find the quantity that you don’t know

L. O. To be able to find an unknown quantity in a given ratio

L. O. To be able to find an unknown quantity in a given ratio