Adam has some green stickers and blue stickers.
If 20 green stickers are added, 80% of the stickers will be blue stickers.
If 135 green stickers are added, 40% of the stickers will be blue stickers.
- How many green stickers are there?
- How many blue stickers are there?
|
Scenario 1 |
Scenario 2 |
|
Green |
Blue |
Green |
Blue |
Before |
1 u - 20 |
4 u |
6 u - 135 |
4 u |
Change |
+ 20 |
No change |
+ 135 |
No change |
After |
1x1 = 1 u |
4x1 = 4 u |
3x2 = 6 u |
2x2 = 4 u |
(a)
80% =
80100 =
4540% =
40100 =
25 Scenario 1 Fraction of the stickers that are green in the end
= 1 -
45 =
15 Scenario 2
Fraction of the stickers that are green in the end
= 1 -
25 =
35 The number of blue stickers remains unchanged in both scenarios.
LCM of 4 and 2 = 4
6 u - 135 = 1 u - 20
6 u - 1 u = 135 - 20
5 u = 115
1 u = 115 ÷ 5 = 23
Number of green stickers
= 1 u - 20
= 1 x 23 - 20
= 23 - 20
= 3
(b)
Number of blue stickers
= 4 u
= 4 x 23
= 92
Answer(s): (a) 3; (b) 92