Bobby and Perry had some cards in the ratio of 11 : 8. Perry and Oscar had some cards in the ratio of 6 : 5. Bobby sold 210 cards to Oscar and ended up with half the number of cards Perry had. How many cards did Oscar have in the end?
| Bobby |
Perry |
Oscar |
| 11x3 |
8x3 |
|
| |
6x4 |
5x4 |
| 33 u |
24 u |
20 u |
The number of cards that Perry had at first is repeated. Make the number of cards that Perry had at first the same. LCM of 8 and 6 is 24.
| |
Bobby |
Perry |
Oscar |
| Before |
33 u |
24 u |
20 u |
| Change |
- 210 |
|
+ 210 |
| After |
12 u |
24 u |
20 u + 210 |
Number of cards that Bobby had in the end
= 24 u ÷ 2
= 12 u
Number of cards that Bobby sold to Oscar
= 33 u - 12 u
= 21 u
21 u = 210
1 u = 210 ÷ 21 = 10
Number of cards that Oscar had in the end
= 20 u + 210
= 20 x 10 + 210
= 200 + 210
= 410
Answer(s): 410
