The ratio of Mark's to Pierre's money is 7 : 8. The ratio of Pierre's to Eric's money is 3 : 4. If Mark has $210, how much more does Eric have than Pierre?
| Mark |
Pierre |
Eric |
| 7x3 |
8x3 |
|
| |
3x8 |
4x8 |
| 21 u |
24 u |
32 u |
The amount that Pierre has is the repeated identity.
Use LCM to make it the same.
LCM of 8 and 3 = 24
Amount that Mark has = 21 u
21 u = 210
1 u = 210 ÷ 21 = 10
Amount that Eric has more than Pierre
= 32 u - 24 u
= 8 u
= 8 x 10
= $80
Answer(s): $80
