Gabby, Cathy and Xylia had a sum of money. The amount of money Gabby had was ²₅ of the amount of money Cathy had. The ratio of the amount of money Cathy had to the total amount of money Xylia and Cathy had was 3: 7. After Xylia gave $85 to Cathy, she had as much money as Cathy. How much more money did Xylia have than Gabby in the end?

Gabby	Cathy	Xylia
2x3 = 6 u	5x3 = 15 u
	3x5 = 15 u	4x5 = 20 u
6 u	15 u	20 u

The amount that Cathy had is the repeated identity. Make the amount that Cathy had the same.  LCM of 5 and 3 is 15.

	Gabby	Cathy	Xylia
Before	6 u	15 u	20 u
Change	No change	+ 85	- 85
After	6 u	15 u + 85	20 u - 85

The amount that Xylia and Cathy 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 Xylia had more than Gabby in the end
= 20 u - 85 - 6 u
= 14 u - 85
= 14 x 34 - 85
= 476 - 85
= $391

Answer(s): $391