Adam has some blue stickers and green stickers.
If 316 blue stickers are added, 40% of the stickers will be green stickers.
If 156 green stickers are added, 10% of the stickers will be blue stickers.
- How many blue stickers are there?
- How many green stickers are there?
|
Scenario 1 |
Scenario 2 |
|
Blue |
Green |
Blue |
Green |
Before |
3 u - 316 |
2 u |
1 p |
9 p - 156 |
Change |
+ 316 |
No change |
No change |
+ 156 |
After |
3 u |
2 u |
1 p |
9 p |
(a)
40% =
40100 =
25 10% =
10100 =
110 Scenario 1 Fraction of the stickers that are blue
= 1 -
25 =
35 Number of blue stickers at first = 3 u - 316
Number of green stickers at first = 2 u
Scenario 2 Fraction of the stickers that are green
= 1 -
110=
910 Number of blue stickers at first = 1 p
Number of green stickers at first = 9 p - 156
3 u - 316 = 1 p --- (1)
2 u = 9 p - 156
2 u + 156 = 9 p --- (2)
(1)
x 9 27 u - 2844 = 9 p --- (3)
(3) = (2)
27 u - 2844 = 2 u + 156
27 u - 2 u = 2844 + 156
25 u = 3000
1 u = 3000 ÷ 25 = 120
Number of blue stickers
= 3 u - 316
= 3 x 120 - 316
= 360 - 316
= 44
(b)
Number of green stickers
= 2 u
= 2 x 120
= 240
Answer(s): (a) 44; (b) 240