Min, Lucy and Mary had a sum of money. The amount of money Min had was
35 of the amount of money Lucy had. The ratio of the amount of money Lucy had to the total amount of money Mary and Lucy had was 4: 9. After Mary gave $95 to Lucy, she had as much money as Lucy. How much more money did Mary have than Min in the end?
Min |
Lucy |
Mary |
3x4 = 12 u |
5x4 = 20 u |
|
|
4x5 = 20 u |
5x5 = 25 u |
12 u |
20 u |
25 u |
The amount that Lucy had is the repeated identity. Make the amount that Lucy had the same. LCM of 5 and 4 is 20.
|
Min |
Lucy |
Mary |
Before |
12 u |
20 u |
25 u |
Change |
No change |
+ 95 |
- 95 |
After |
12 u |
20 u + 95 |
25 u - 95 |
The amount that Mary and Lucy had in the end is the same.
25 u - 95 = 20 u + 95
25 u - 20 u = 95 + 95
5 u = 190
1 u = 190 ÷ 5 = 38
Amount that Mary had more than Min in the end
= 25 u - 95 - 12 u
= 13 u - 95
= 13 x 38 - 95
= 494 - 95
= $399
Answer(s): $399