The ratio of the number of red stamps to blue stamps is 9 : 2. After Asher gives away 50 red stamps and buys another 90 blue stamps, there is equal number of red stamps and blue stamps. How many stamps does Asher have now?
| |
Red |
Blue |
| Before |
9 u |
2 u |
| Change |
- 50 |
+ 90 |
| After |
9 u - 50 |
2 u + 90 |
The number of red stamps and blue stamps in the end is the same.
9 u - 50 = 2 u + 90
9 u - 2 u = 90 + 50
7 u = 140
1 u = 140 ÷ 7 = 20
Number of stamps that Asher has now
= 9 u - 50 + 2 u + 90
= 9 u + 2 u - 50 + 90
= 11 u + 40
= 11 x 20 + 40
= 220 + 40
= 260
Answer(s): 260
