The ratio of the number of green stickers to blue stickers is 9 : 7.
After Adam gives away 40 green stickers and 30 blue stickers,
there is an equal number of green stickers and blue stickers.
How many stickers does Adam have now?
|
Green |
Blue |
Before |
9 u |
7 u |
Change |
- 40 |
- 30 |
After |
9 u - 40 |
7 u - 30 |
The number of green stickers and blue stickers in the end is the same.
9 u - 40 = 7 u - 30
9 u - 7 u = 40 - 30
2 u = 10
1 u = 10 ÷ 2 = 5
Number of stickers that Adam has now
= 9 u - 40 + 7 u - 30
= 9 u + 7 u - 40 - 30
= 16 u - 70
= 16 x 5 - 70
= 80 - 70
= 10
Answer(s): 10