The ratio of the number of red stickers to green stickers is 9 : 7.
After Adam gives away 40 red stickers and 10 green stickers,
there is an equal number of red stickers and green stickers.
How many stickers does Adam have now?
|
Red |
Green |
Before |
9 u |
7 u |
Change |
- 40 |
- 10 |
After |
9 u - 40 |
7 u - 10 |
The number of red stickers and green stickers in the end is the same.
9 u - 40 = 7 u - 10
9 u - 7 u = 40 - 10
2 u = 30
1 u = 30 ÷ 2 = 15
Number of stickers that Adam has now
= 9 u - 40 + 7 u - 10
= 9 u + 7 u - 40 - 10
= 16 u - 50
= 16 x 15 - 50
= 240 - 50
= 190
Answer(s): 190