The number of red and green stickers are equal.
If Adam gives away 90 red stickers and 30 green stickers,
the ratio of red stickers to green stickers becomes 3 : 7.
How many stickers are there at first?
|
Red |
Green |
Before |
3 u + 90 |
7 u + 30 |
Change |
- 90 |
- 30 |
After |
3 u |
7 u |
The number of red and green stickers is the same at first.
3 u + 90 = 7 u + 30
7 u - 3 u = 90 - 30
4 u = 60
1 u = 60 ÷ 4 = 15
Number of stickers that Adam has at first
= 3 u + 90 + 7 u + 30
= 3 u + 7 u + 90 + 30
= 10 u + 120
= 10 x 15 + 120
= 150 + 120
= 270
Answer(s): 270