The ratio of the number of green stickers to red stickers is 3 : 1. After Vaidev gives away 20 green stickers and buys another 70 red stickers, there is equal number of green stickers and red stickers. How many stickers does Vaidev have now?
| |
Green |
Red |
| Before |
3 u |
1 u |
| Change |
- 20 |
+ 70 |
| After |
3 u - 20 |
1 u + 70 |
The number of green stickers and red stickers in the end is the same.
3 u - 20 = 1 u + 70
3 u - 1 u = 70 + 20
2 u = 90
1 u = 90 ÷ 2 = 45
Number of stickers that Vaidev has now
= 3 u - 20 + 1 u + 70
= 3 u + 1 u - 20 + 70
= 4 u + 50
= 4 x 45 + 50
= 180 + 50
= 230
Answer(s): 230
