The ratio of Ahmad's to Sean's money is 7 : 5. The ratio of Sean's to Brandon's money is 3 : 4. If Ahmad has $210, how much less does Sean have than Brandon?
| Ahmad |
Sean |
Brandon |
| 7x3 |
5x3 |
|
| |
3x5 |
4x5 |
| 21 u |
15 u |
20 u |
The amount that Sean has is the repeated identity.
Use LCM to make it the same.
LCM of 5 and 3 = 15
Amount that Ahmad has = 21 u
21 u = 210
1 u = 210 ÷ 21 = 10
Amount that Sean has less than Brandon
= 20 u - 15 u
= 5 u
= 5 x 10
= $50
Answer(s): $50
