The ratio of Jeremy's to Mark's money is 4 : 7. The ratio of Mark's to Billy's money is 3 : 4. If Jeremy has $180, how much more does Billy have than Mark?
| Jeremy |
Mark |
Billy |
| 4x3 |
7x3 |
|
| |
3x7 |
4x7 |
| 12 u |
21 u |
28 u |
The amount that Mark has is the repeated identity.
Use LCM to make it the same.
LCM of 7 and 3 = 21
Amount that Jeremy has = 12 u
12 u = 180
1 u = 180 ÷ 12 = 15
Amount that Billy has more than Mark
= 28 u - 21 u
= 7 u
= 7 x 15
= $105
Answer(s): $105
