Adam has 350 stickers in 3 colours.
40% of the stickers are green.
The number of blue stickers and red in the ratio of 3 : 7.
- What percentage of the stickers is red?
- How many blue stickers are there?
Green |
Blue |
Red |
Total |
2 x 10 |
3 x 10 |
5 x 10 |
|
3 x 3 |
7 x 3 |
|
20 u |
9 u |
21 u |
50 u |
(a)
40% =
40100 =
25 The number of blue and red stickers is the combined repeated identity.
Make the number of blue and red stickers the same using the LCM of 3 and 10.
LCM of 3 and 10 = 30
Percentage of the stickers that is red
=
2150 x 100%
= 42%
(b)
Total number of stickers = 50 u
50 u = 350
1 u = 350 ÷ 50 = 7
Number of blue stickers
= 9 u
= 9 x 7
= 63
Answer(s): (a) 42%; (b) 63