The ratio of the number of red stickers to blue stickers is 7 : 5.
After Adam gives away 70 red stickers and 40 blue stickers,
there is an equal number of red stickers and blue stickers.
How many stickers does Adam have now?
|
Red |
Blue |
Before |
7 u |
5 u |
Change |
- 70 |
- 40 |
After |
7 u - 70 |
5 u - 40 |
The number of red stickers and blue stickers in the end is the same.
7 u - 70 = 5 u - 40
7 u - 5 u = 70 - 40
2 u = 30
1 u = 30 ÷ 2 = 15
Number of stickers that Adam has now
= 7 u - 70 + 5 u - 40
= 7 u + 5 u - 70 - 40
= 12 u - 110
= 12 x 15 - 110
= 180 - 110
= 70
Answer(s): 70