Adam has some green stickers and red stickers.
If Adam receives another 468 red stickers,
the green stickers will be 25% as many as the red stickers.
If Adam receives another 21 green stickers,
the green stickers will be 75% as many as the red stickers.
- How many green stickers are there?
- How many red stickers are there?
|
Scenario 1 |
Scenario 2 |
|
Green |
Red |
Green |
Red |
Before |
1 u |
4 u - 468 |
3 p - 21 |
4 p |
Change |
No change |
+ 468 |
+ 21 |
No change |
After |
1 u |
4 u |
3 p |
4 p |
(a)
25% =
25100 =
14 75% =
75100 =
34 Scenario 1 Number of green stickers at first = 1 u
Number of red stickers at first = 4 u - 468
Scenario 2 Number of green stickers at first = 3 p - 21
Number of red stickers at first = 4 p
1 u = 3 p - 21 --- (1)
4 u - 468 = 4 p --- (2)
(2)
÷ 41 u - 117 = 1 p
1 u = 1 p + 117 --- (3)
(1) = (3)
3 p - 21 = 1 p + 117
3 p - 1 p = 21 + 117
2 p = 138
1 p = 138 ÷ 2 = 69
Number of green stickers
= 3 p - 21
= 3 x 69 - 21
= 207 - 21
= 186
(b)
Number of red stickers
= 4 p
= 4 x 69
= 276
Answer(s): (a) 186; (b) 276