Min, Rachel and Irene had a sum of money. The amount of money Min had was
25 of the amount of money Rachel had. The ratio of the amount of money Rachel had to the total amount of money Irene and Rachel had was 3: 7. After Irene gave $85 to Rachel, she had as much money as Rachel. How much more money did Irene have than Min in the end?
Min |
Rachel |
Irene |
2x3 = 6 u |
5x3 = 15 u |
|
|
3x5 = 15 u |
4x5 = 20 u |
6 u |
15 u |
20 u |
The amount that Rachel had is the repeated identity. Make the amount that Rachel had the same. LCM of 5 and 3 is 15.
|
Min |
Rachel |
Irene |
Before |
6 u |
15 u |
20 u |
Change |
No change |
+ 85 |
- 85 |
After |
6 u |
15 u + 85 |
20 u - 85 |
The amount that Irene and Rachel had in the end is the same.
20 u - 85 = 15 u + 85
20 u - 15 u = 85 + 85
5 u = 170
1 u = 170 ÷ 5 = 34
Amount that Irene had more than Min in the end
= 20 u - 85 - 6 u
= 14 u - 85
= 14 x 34 - 85
= 476 - 85
= $391
Answer(s): $391