The ratio of the number of red stamps to blue stamps is 8 : 3. After Rael gives away 20 red stamps and buys another 50 blue stamps, there is equal number of red stamps and blue stamps. How many stamps does Rael have now?
| |
Red |
Blue |
| Before |
8 u |
3 u |
| Change |
- 20 |
+ 50 |
| After |
8 u - 20 |
3 u + 50 |
The number of red stamps and blue stamps in the end is the same.
8 u - 20 = 3 u + 50
8 u - 3 u = 50 + 20
5 u = 70
1 u = 70 ÷ 5 = 14
Number of stamps that Rael has now
= 8 u - 20 + 3 u + 50
= 8 u + 3 u - 20 + 50
= 11 u + 30
= 11 x 14 + 30
= 154 + 30
= 184
Answer(s): 184
