Adam has 380 stickers in 3 colours.
60% of the stickers are green.
The number of red stickers and blue in the ratio of 3 : 5.
- What percentage of the stickers is blue?
- How many red stickers are there?
Green |
Red |
Blue |
Total |
3 x 4 |
2 x 4 |
5 x 4 |
|
3 x 1 |
5 x 1 |
|
12 u |
3 u |
5 u |
20 u |
(a)
60% =
60100 =
35 The number of red and blue stickers is the combined repeated identity.
Make the number of red and blue stickers the same using the LCM of 2 and 8.
LCM of 2 and 8 = 8
Percentage of the stickers that is blue
=
520 x 100%
= 25%
(b)
Total number of stickers = 20 u
20 u = 380
1 u = 380 ÷ 20 = 19
Number of red stickers
= 3 u
= 3 x 19
= 57
Answer(s): (a) 25%; (b) 57