The ratio of David's to Tommy's money is 5 : 4. The ratio of Tommy's to Ian's money is 3 : 5. If David has $300, how much more does Ian have than Tommy?
| David |
Tommy |
Ian |
| 5x3 |
4x3 |
|
| |
3x4 |
5x4 |
| 15 u |
12 u |
20 u |
The amount that Tommy has is the repeated identity.
Use LCM to make it the same.
LCM of 4 and 3 = 12
Amount that David has = 15 u
15 u = 300
1 u = 300 ÷ 15 = 20
Amount that Ian has more than Tommy
= 20 u - 12 u
= 8 u
= 8 x 20
= $160
Answer(s): $160
