Adam has 100 stickers in 3 colours.
30% of the stickers are green.
The number of red stickers and blue in the ratio of 2 : 3.
- What percentage of the stickers is blue?
- How many red stickers are there?
Green |
Red |
Blue |
Total |
3 x 5 |
7 x 5 |
10 x 5 |
|
2 x 7 |
3 x 7 |
|
15 u |
14 u |
21 u |
50 u |
(a)
30% =
30100 =
310 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 7 and 5.
LCM of 7 and 5 = 35
Percentage of the stickers that is blue
=
2150 x 100%
= 42%
(b)
Total number of stickers = 50 u
50 u = 100
1 u = 100 ÷ 50 = 2
Number of red stickers
= 14 u
= 14 x 2
= 28
Answer(s): (a) 42%; (b) 28