The ratio of the number of green erasers to blue erasers is 8 : 3. After Will gives away 50 green erasers and buys another 60 blue erasers, there is equal number of green erasers and blue erasers. How many erasers does Will have now?
| |
Green |
Blue |
| Before |
8 u |
3 u |
| Change |
- 50 |
+ 60 |
| After |
8 u - 50 |
3 u + 60 |
The number of green erasers and blue erasers in the end is the same.
8 u - 50 = 3 u + 60
8 u - 3 u = 60 + 50
5 u = 110
1 u = 110 ÷ 5 = 22
Number of erasers that Will has now
= 8 u - 50 + 3 u + 60
= 8 u + 3 u - 50 + 60
= 11 u + 10
= 11 x 22 + 10
= 242 + 10
= 252
Answer(s): 252
