The ratio of the number of green beads to red beads is 5 : 3. After Ahmad gives away 20 green beads and buys another 70 red beads, there is equal number of green beads and red beads. How many beads does Ahmad have now?
|
Green |
Red |
Before |
5 u |
3 u |
Change |
- 20 |
+ 70 |
After |
5 u - 20 |
3 u + 70 |
The number of green beads and red beads in the end is the same.
5 u - 20 = 3 u + 70
5 u - 3 u = 70 + 20
2 u = 90
1 u = 90 ÷ 2 = 45
Number of beads that Ahmad has now
= 5 u - 20 + 3 u + 70
= 5 u + 3 u - 20 + 70
= 8 u + 50
= 8 x 45 + 50
= 360 + 50
= 410
Answer(s): 410