The ratio of the number of red stickers to green stickers is 5 : 3.
After Adam gives away 20 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 |
5 u |
3 u |
Change |
- 20 |
- 10 |
After |
5 u - 20 |
3 u - 10 |
The number of red stickers and green stickers in the end is the same.
5 u - 20 = 3 u - 10
5 u - 3 u = 20 - 10
2 u = 10
1 u = 10 ÷ 2 = 5
Number of stickers that Adam has now
= 5 u - 20 + 3 u - 10
= 5 u + 3 u - 20 - 10
= 8 u - 30
= 8 x 5 - 30
= 40 - 30
= 10
Answer(s): 10