The ratio of the number of red beads to blue beads is 5 : 3. After Daniel gives away 20 red beads and buys another 80 blue beads, there is equal number of red beads and blue beads. How many beads does Daniel have now?
| |
Red |
Blue |
| Before |
5 u |
3 u |
| Change |
- 20 |
+ 80 |
| After |
5 u - 20 |
3 u + 80 |
The number of red beads and blue beads in the end is the same.
5 u - 20 = 3 u + 80
5 u - 3 u = 80 + 20
2 u = 100
1 u = 100 ÷ 2 = 50
Number of beads that Daniel has now
= 5 u - 20 + 3 u + 80
= 5 u + 3 u - 20 + 80
= 8 u + 60
= 8 x 50 + 60
= 400 + 60
= 460
Answer(s): 460
