The ratio of the number of blue beads to red beads is 9 : 4. After Valen gives away 60 blue beads and buys another 90 red beads, there is equal number of blue beads and red beads. How many beads does Valen have now?
| |
Blue |
Red |
| Before |
9 u |
4 u |
| Change |
- 60 |
+ 90 |
| After |
9 u - 60 |
4 u + 90 |
The number of blue beads and red beads in the end is the same.
9 u - 60 = 4 u + 90
9 u - 4 u = 90 + 60
5 u = 150
1 u = 150 ÷ 5 = 30
Number of beads that Valen has now
= 9 u - 60 + 4 u + 90
= 9 u + 4 u - 60 + 90
= 13 u + 30
= 13 x 30 + 30
= 390 + 30
= 420
Answer(s): 420
