The ratio of the number of red stickers to green stickers is 9 : 4.
After Adam gives away 30 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 |
4 u |
Change |
- 30 |
- 10 |
After |
9 u - 30 |
4 u - 10 |
The number of red stickers and green stickers in the end is the same.
9 u - 30 = 4 u - 10
9 u - 4 u = 30 - 10
5 u = 20
1 u = 20 ÷ 5 = 4
Number of stickers that Adam has now
= 9 u - 30 + 4 u - 10
= 9 u + 4 u - 30 - 10
= 13 u - 40
= 13 x 4 - 40
= 52 - 40
= 12
Answer(s): 12