The number of red and blue stickers are equal.
If Adam gives away 70 red stickers and 40 blue stickers,
the ratio of red stickers to blue stickers becomes 4 : 7.
How many stickers are there at first?
|
Red |
Blue |
Before |
4 u + 70 |
7 u + 40 |
Change |
- 70 |
- 40 |
After |
4 u |
7 u |
The number of red and blue stickers is the same at first.
4 u + 70 = 7 u + 40
7 u - 4 u = 70 - 40
3 u = 30
1 u = 30 ÷ 3 = 10
Number of stickers that Adam has at first
= 4 u + 70 + 7 u + 40
= 4 u + 7 u + 70 + 40
= 11 u + 110
= 11 x 10 + 110
= 110 + 110
= 220
Answer(s): 220