The ratio of Oscar's to Sean's money is 8 : 9. The ratio of Sean's to Archie's money is 3 : 5. If Oscar has $88, how much less does Sean have than Archie?
| Oscar |
Sean |
Archie |
| 8x1 |
9x1 |
|
| |
3x3 |
5x3 |
| 8 u |
9 u |
15 u |
The amount that Sean has is the repeated identity.
Use LCM to make it the same.
LCM of 9 and 3 = 9
Amount that Oscar has = 8 u
8 u = 88
1 u = 88 ÷ 8 = 11
Amount that Sean has less than Archie
= 15 u - 9 u
= 6 u
= 6 x 11
= $66
Answer(s): $66
