Ratio

1
Ratio

• Is all about sharing and being fair

2
Ratio

• Ratio is used to share things out when we are
  being fair.
• It is also used when one thing has a greater
  representation than another.

3
Ratio

• What is the ratio of red counters to yellow?
• We write this as 5 3
• (538 and there are 8 counters)

4
Ratio

• What is the ratio of green counters to blue?

4 5
5
Ratio

• What is the ratio of red counters to yellow?
• We could write this as 6 2
• We could also write it as 3 1

6
Ratio

• We call this simplifying the ratio

7
4 8
What is the ratio of blue to yellow?
1 2
8
5 10
What is the ratio of red to green?
1 2
9
12 2
What is the ratio of yellow to blue?
6 1
10
6 9
What is the ratio of green to red?
2 3
11
Ratio

• Its your turn!!
• Complete the exercises on the sheet.
• Stick the sheet into your books.

12
Ratio

• Example
• Friends Bill and Betty buy a 1 lottery ticket.
• Bill pays 60p and Betty the other 40p.
• They win 1000.
• Should they get 500 each?

13
Ratio

• They might be really good friends and decide to
  go halves.
• However, it would be a more fair way to split the
  winnings in the same ratio as they paid.
• How much would they get?

14
Ratio

• The lottery ticket was paid for by splitting the
  cost 60 to 40.
• As a ratio, we would write this as
• 60 40

15
Ratio

• 60 40
• Means that Bill will get 60 parts to Bettys 40
• Between them there are 100 parts

16
Ratio

• For 1000, I need to share 100 ten times.
• 60 40 ten times is
• 600 400
• So Bill gets 600 and Betty gets 400 from their
  winnings.

17
What is the ratio of black counters to white? _______ Simplify you answer _______ What is the ratio of black counters to white? _______ Simplify you answer _______
What is the ratio of white counters to black? _______ Simplify you answer _______ What is the ratio of black counters to white? _______ Simplify you answer _______
What is the ratio of black counters to white? _______ Simplify you answer _______ What is the ratio of white counters to black? _______ Simplify you answer _______
What is the ratio of white counters to black? _______ Simplify you answer _______ What is the ratio of black counters to white? _______ Simplify you answer _______

• Shade in the counters to represent the given
  ratios of black to white.
• 41
• 25
• 13
• 53
• 72
• 65
• 51
• 32
• 75
• 11

24
62
12
31
43
210
43
15
83
153
83
51
36
33
12
11
18
What is the ratio of black counters to white? _______ Simplify your answer _______ What is the ratio of black counters to white? _______ Simplify your answer _______
What is the ratio of white counters to black? _______ Simplify your answer _______ What is the ratio of black counters to white? _______ Simplify your answer _______
What is the ratio of black counters to white? _______ Simplify your answer _______ What is the ratio of white counters to black? _______ Simplify your answer _______
What is the ratio of white counters to black? _______ Simplify your answer _______ What is the ratio of black counters to white? _______ Simplify your answer _______

• Shade in the counters to represent the given
  ratios of black to white.
• 41
• 25
• 13
• 53
• 72
• 65
• 51
• 32
• 75
• 11