Adam has some green stickers and red stickers.
If Adam receives another 865 red stickers,
the green stickers will be 20% as many as the red stickers.
If Adam receives another 70 green stickers,
the green stickers will be 80% 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 |
5 u - 865 |
4 p - 70 |
5 p |
Change |
No change |
+ 865 |
+ 70 |
No change |
After |
1 u |
5 u |
4 p |
5 p |
(a)
20% =
20100 =
15 80% =
80100 =
45 Scenario 1 Number of green stickers at first = 1 u
Number of red stickers at first = 5 u - 865
Scenario 2 Number of green stickers at first = 4 p - 70
Number of red stickers at first = 5 p
1 u = 4 p - 70 --- (1)
5 u - 865 = 5 p --- (2)
(2)
÷ 51 u - 173 = 1 p
1 u = 1 p + 173 --- (3)
(1) = (3)
4 p - 70 = 1 p + 173
4 p - 1 p = 70 + 173
3 p = 243
1 p = 243 ÷ 3 = 81
Number of green stickers
= 4 p - 70
= 4 x 81 - 70
= 324 - 70
= 254
(b)
Number of red stickers
= 5 p
= 5 x 81
= 405
Answer(s): (a) 254; (b) 405