The ratio of Tommy's to Paul's money is 7 : 4. The ratio of Paul's to Mark's money is 3 : 5. If Tommy has $378, how much less does Paul have than Mark?
| Tommy |
Paul |
Mark |
| 7x3 |
4x3 |
|
| |
3x4 |
5x4 |
| 21 u |
12 u |
20 u |
The amount that Paul has is the repeated identity.
Use LCM to make it the same.
LCM of 4 and 3 = 12
Amount that Tommy has = 21 u
21 u = 378
1 u = 378 ÷ 21 = 18
Amount that Paul has less than Mark
= 20 u - 12 u
= 8 u
= 8 x 18
= $144
Answer(s): $144
