If Hazel gives Zeph $15, the amount of money she has will be 30% of his. If Zeph gives Hazel $111, he will have the same amount of money as her. How much money did each of them have?
(a) Zeph
(b) Hazel

	Case 1		Case 2
	Zeph	Hazel	Zeph	Hazel
Before	10 u - 15	3 u + 15	6.5 u + 111	6.5 u - 111
Change	+ 15	- 15	- 111	+ 111
After	10 u	3 u	6.5 u	6.5 u

(a)
30% = ³⁰₁₀₀ = ³₁₀

In Case 1, when Hazel gives to Zeph, there is an internal transfer of money from Hazel to Zeph.  The total amount that both have remains the same.

In Case 2, when Zeph gives to Hazel, there is an internal transfer of money from Zeph to Hazel. The total amount that both have remains the same.

The total amount that both have in Case 1 and Case 2 are the same.

Total amount that Hazel and Zeph have
= 10 u + 3 u
= 13 u

Amount that Hazel and Zeph each has in the end for Case 2
= 13 u ÷ 2
= 6.5 u

Amount that Zeph has at first is the same in Case 1 and Case 2.

10 u - 15 = 6.5 u + 111
10 u - 6.5 u = 111 + 15
3.5 u = 126 

1 u = 126 ÷ 3.5 = 36

Amount that Zeph has
= 10 u - 15
= 10 x 36 - 15
= 360 - 15
= $345 

(b)
Amount that Hazel has
= 3 u + 15
= 3 x 36 + 15
= 108 + 15
= $123

Answer(s): (a) $345; (b) $123