Untitled Lesson

RATIO Unit 21

� Use ratios

� Use equivalent ratios

� Complete calculations using ratio

� Divided quantity into proportional parts

� Solve problems using direct and indirect ratios

� Apply ratio to currency and scale drawing.

Cancelling down ratio

A farmer uses 20 bags of fertilizer for four fields. What is the
ratio of fields to bags?

Sonya tiles her bathroom using 96 plain and 12 patterned
tiles. What is the ratio of patterned to plain tiles?

Bags : Fields
20 : 4
5 : 1

Plain : Patterned
96 : 12
8 : 1

Cancelling down ratio

A farmer uses 20 bags of fertilizer for four fields. What is the
ratio of fields to bags?

Fields : Bags
4 : 20

If the farmer had 34 bags of fertilizer what is the maximum
number of fields he can cover?

1 : 5

Cancelling down ratio

Sonya tiles her bathroom using 96 plain and 12 patterned
tiles. What is the ratio of patterned to plain tiles?

Patterned : Plain
12 : 96
1 : 8

If Sonya had 5 patterned tiles How many plain would she
need?
What fraction of the tiles in the bathroom are patterned?

Simplify the following ratios

4 : 6

15 : 10

6 : 18

45 : 10

24 : 36

27 : 63

2.5 : 4.5

6 : 1.2

3:2

4 : 62 : 3

3 : 2
1 : 3

9 : 2

2 : 3

3 : 7

5 : 9

5 : 1

Xander and William share some chocolate.
Xander has 180g and William has 240g. Give the
ratio of Xander’s share to William’s share, in its
simplest form.

Zach and Yvonne share £400. Zach gets £280 and
Yvonne gets the rest. Give the ratio of Yvonne’s
share to Zack’s share, in its simplest form.

Vernon and Sam share some money. Sam gets
£3.60. Vernon gets 80p more than Sam. Give the
ratio of Vernon’s share to Sam’s share in its
simplest form.

Give the ratio of prime numbers to square numbers
from the whole numbers from 1-20. Give your
answer in its simplest form.

Pamela, Queenie and Olivia share £600. Pamela
gets £200 and Queenie gets £40 more than
Olivia. Give the ratio of Olivia’s money to
Pamela’s money to Queenie’s money, in its
simplest form.

Simplify the following ratios

1 hour to 15 mins

95p to £3.00

400m to 1.5km

4500ml to 2 litres

4 : 1
19 : 60

4 : 15
9 : 4

RATI

O

In a house there are 3 cats and 2 dogs.

Cats : Dogs

3 : 2

60% : 40%

RATIO

A drink needs 150ml of orange and 450ml of
lemon.
What is the ratio to lemon to orange?

lemon orange

450 : 150

3 : 1

What percentage of the drink is lemon?

RATI

O

1.2 : 2.4

12 : 24

1 : 2

x 10

÷ 12

Express the following ratios in the form 1 : n

Express the following ratios in the form 1 : n

2 : 3

5 : 4

10 : 7

8 : 13

21 : 40

4 : 10

Circle the value of x

a : b = 1 : 6

a : c = 3 : 1

How many times bigger is b than c?

e : f = 2 : 3 and f : g = 5 : 4

Work out e : g

Give your answer in its simplest form.

A toy box contains red, yellow, blue and green bricks.

25% of the bricks are red.There are 12 yellow bricks.

The ratio yellow to blue to green is 2 : 3 : 1

Show that there are 48 bricks in the box

The total cost of 15 cinema tickets is £104.25.

What is the cost of 8 tickets?

Ratio problem

£104.25 ÷ 15 = £6.95

Cost of 1 ticket

£6.95 x 8 = £55.60

Cost of 8 ticket

Questions

1.

A taxi firm buys 2 cars for £26 000. How much would 5
cars cost?

2.

A stair carpet cost £64 for 8m2. How much would 21m2
cost?

3.

A car used 4 gallons of petrol to travel 200 miles. How far
will it travel on 9 gallons of petrol?

Questions

1.

A taxi firm buys 2 cars for £26 000. How much would 5
cars cost?

£26 000 ÷ 2 = £13 000 each car

£13 000 X 5 = £65 000 for 5 cars

2.

A stair carpet cost £64 for 8m2. How much would 21m2
cost?

£64 ÷ 8 = £8 per 1m2 so £8 x 21 = £168 for 21m2

3.

A car used 4 gallons of petrol to travel 200 miles. How far
will it travel on 9 gallons of petrol?

200 miles ÷ 4 gallons = 50 miles per gallon

So 9 gallons x 50 miles = 450 miles on 9 gallons

Orange Squash

The label on a bottle of orange drink states:-

Dilute

orange drink : water

1 : 4

How much water should be added
to a jug containing 120 ml of orange
drink?

How much drink will be made in
total?

Orange : Water
1 : 4
120 ml

480 ml

Total 120 + 480 = 600 ml

Making Paint

I am mixing paint, I need red and white in the ratio
2:3.
I have 10 litres of red, how much white do I need?

x 5

x 5

I need 15 litres of white

Red

:

White

2

:

3

10

:

15

RATIO

The ratio of female to male members of a local
club is 5:3.
If there are 160 female members what is the total
membership?

female male

5 : 3

160 :

1 part is 160 ÷ 5 = 32

3 parts are 32 x 3 = 96

96

Total membership160 + 96 = 256

Recipes

Pancakes

Makes 8 pancakes

Ingredients
125 g plain flour
1 medium size egg, beaten
300 ml milk
a little oil for frying

Work out the ingredients needed for
30 pancakes.

Sally, Bill and James play a lottery syndicate. Sally pays £2,
Bill pays £3 and James pays £5. They share the winning in
the same ratio.

Last week they won £120.

How much did each person receive?

Splitting Ratio

Sally

Bill

James

2

3

5

Last week they won £120. How much did each person receive?

Sally

Bill

James

2

3

5

£24

£36

£60

Splitting Ratio

Concrete is mixed using cement, sand and gravel in the ratio
of 1:3:6.

If 60 kg of concrete is needed, what amount of each item is
needed ?

Cement

Sand

Gravel

1

3

6

6

18

36

Splitting Ratio

A sample of punch is made from lemonade, orange juice and
pineapple juice in the ratio 9 : 4 : 5.

How much of each would be needed to make 27 litres?

Lemonade

Orange

Pineapple

9

4

5

13.5

6

7.5

A gardener wants to make a display of red and yellow tulips.
He orders red and yellow tulip bulbs in the ratio 3 : 5. He
orders a total of 2000 bulbs. How many of each colour bulb
will he get?

Three business partners Kevin, John and Margaret, put
money into a venture in the ratio 3 : 4 : 5.

They share any profits in the same ratio. Last year, Margaret
received £3 600 from the profits. How much did Kevin and
John receive?

Divide 5 hours in the ratio 7 : 5

x

y

z

The angles in this triangle (x, y and z) are in the
ratio 5:1:3 find the size of the angles.

RATIO Measures

1 inch = 2.5 cm

Given that 1 inch = 2.5 cm, what is 12 inches in cm?

12 inch = 30 cm
x 12
2.5 x 12 = 30

RATIO Currency

£ : Euro

1 : 1.131

Given that £1 = €1.131, how many Euros would you receive for £150?

150 : 169.65
x 150

150 x1.131 =169.65

It usually takes five workers six days each to spring clean a
factory.

How many workers would be needed to clean the factory in
2 days?

Indirect Ratio

The job takes

5 x 6 = 30 working days to complete

30 working days ÷ 2 = 15 workers needed

A job takes 3 workers 6 days each to complete.

How long would it take for 4 workers to complete.

Indirect Ratio

The job takes

3 x 6 = 18 working days to complete

18 days split between 4 workers

18 ÷ 4 = 4.5 days each