Ratio and Proportion

1
Ratio and Proportion
2
Objectives

• Use proportion to solve problems.
• Use direct proportion in simple contexts.

Vocabulary
proportion
ratio
multiplicative
3
Finding multiplicative relationships
Example
or
8 is ¼ of 32
34 is twice as big as 17.
Find 5 other multiplicative relationships in the
target board.
4
Share the amounts highlighted equally between 2.
24 sweets
60
Share the amounts highlighted equally between 3.
5 kg
8p
Share the amounts highlighted equally between 4.
3
5
Unequal sharing
If my brother and I shared 12 so that he
received half as much as I did how much would
we each receive?
2 lots (me)
12 into 3 lots
Each lot 4
12
Me, 2 lots of 4 8
1 lot (my brother)
My brother, 1 lot of 4 4
6
Share the highlighted amounts so that one person
gets half as much as the other.
60p shared unequally is 20p 40p
These amounts have been shared in the ratio 12
6 CDs shared unequally is 2 CDs 4 CDs
15 shared unequally is 5 10
7
How many eggs for 4 people?
4 people need 2 eggs
How much flour for 6 people?
300g of flour for 6 people
How much salt for 10 people?
20g of salt for 10 people
8
Recipes
Using the information in the box find
Salad for three 200g lettuce 100g tomatoes 50g
onions 50 g cheese
The ingredients for salad for 9 people.
The ingredients for pie for 8 people.
Pie for two 200g flour 50g margarine 1 egg
beaten 500g beef
9
Answers
Recipes
Salad for three 200g lettuce 100g tomatoes 50g
onions 50 g cheese
The ingredients for salad for 9 people.
600g lettuce 300g tomatoes 150g onions 150g cheese
The ingredients for pie for 8 people.
Pie for two 200g flour 50g margarine 1 egg
beaten 500g beef
800g flour 200g margarine 4 eggs beaten 2000g beef
10
Objectives

• Use proportion to solve problems.
• Use direct proportion in simple contexts.

Vocabulary
proportion
ratio
multiplicative
11
Thank you for your attention