The ratio of the number of blue beads to red beads is 8 : 3. After Tim gives away 30 blue beads and buys another 40 red beads, there is equal number of blue beads and red beads. How many beads does Tim have now?
| |
Blue |
Red |
| Before |
8 u |
3 u |
| Change |
- 30 |
+ 40 |
| After |
8 u - 30 |
3 u + 40 |
The number of blue beads and red beads in the end is the same.
8 u - 30 = 3 u + 40
8 u - 3 u = 40 + 30
5 u = 70
1 u = 70 ÷ 5 = 14
Number of beads that Tim has now
= 8 u - 30 + 3 u + 40
= 8 u + 3 u - 30 + 40
= 11 u + 10
= 11 x 14 + 10
= 154 + 10
= 164
Answer(s): 164
