The ratio of the number of red stickers to blue stickers is 7 : 5.
After Adam gives away 50 red stickers and 30 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 |
- 50 |
- 30 |
After |
7 u - 50 |
5 u - 30 |
The number of red stickers and blue stickers in the end is the same.
7 u - 50 = 5 u - 30
7 u - 5 u = 50 - 30
2 u = 20
1 u = 20 ÷ 2 = 10
Number of stickers that Adam has now
= 7 u - 50 + 5 u - 30
= 7 u + 5 u - 50 - 30
= 12 u - 80
= 12 x 10 - 80
= 120 - 80
= 40
Answer(s): 40