The ratio of the number of blue beads to green beads is 3 : 1. After Dylan gives away 20 blue beads and buys another 30 green beads, there is equal number of blue beads and green beads. How many beads does Dylan have now?
| |
Blue |
Green |
| Before |
3 u |
1 u |
| Change |
- 20 |
+ 30 |
| After |
3 u - 20 |
1 u + 30 |
The number of blue beads and green beads in the end is the same.
3 u - 20 = 1 u + 30
3 u - 1 u = 30 + 20
2 u = 50
1 u = 50 ÷ 2 = 25
Number of beads that Dylan has now
= 3 u - 20 + 1 u + 30
= 3 u + 1 u - 20 + 30
= 4 u + 10
= 4 x 25 + 10
= 100 + 10
= 110
Answer(s): 110
