Erika, Jean and Jade had a sum of money. The amount of money Erika had was ³₄ of the amount of money Jean had. The ratio of the amount of money Jean had to the total amount of money Jade and Jean had was 3: 7. After Jade gave $12 to Jean, she had as much money as Jean. How much more money did Jade have than Erika in the end?

Erika	Jean	Jade
3x3 = 9 u	4x3 = 12 u
	3x4 = 12 u	4x4 = 16 u
9 u	12 u	16 u

The amount that Jean had is the repeated identity. Make the amount that Jean had the same.  LCM of 4 and 3 is 12.

	Erika	Jean	Jade
Before	9 u	12 u	16 u
Change	No change	+ 12	- 12
After	9 u	12 u + 12	16 u - 12

The amount that Jade and Jean had in the end is the same.

16 u - 12 = 12 u + 12
16 u - 12 u = 12 + 12 
4 u = 24

1 u = 24 ÷ 4 = 6

Amount that Jade had more than Erika in the end
= 16 u - 12 - 9 u
= 7 u - 12
= 7 x 6 - 12
= 42 - 12
= $30

Answer(s): $30