The number of red and blue stickers are equal.
If Adam gives away 80 red stickers and 60 blue stickers,
the ratio of red stickers to blue stickers becomes 3 : 7.
How many stickers are there at first?
|
Red |
Blue |
Before |
3 u + 80 |
7 u + 60 |
Change |
- 80 |
- 60 |
After |
3 u |
7 u |
The number of red and blue stickers is the same at first.
3 u + 80 = 7 u + 60
7 u - 3 u = 80 - 60
4 u = 20
1 u = 20 ÷ 4 = 5
Number of stickers that Adam has at first
= 3 u + 80 + 7 u + 60
= 3 u + 7 u + 80 + 60
= 10 u + 140
= 10 x 5 + 140
= 50 + 140
= 190
Answer(s): 190