If Yoko gives Ryan $35, the amount of money she has will be 25% of his. If Ryan gives Yoko $1, he will have the same amount of money as her. How much money did each of them have?
(a) Ryan
(b) Yoko

	Case 1		Case 2
	Ryan	Yoko	Ryan	Yoko
Before	4 u - 35	1 u + 35	2.5 u + 1	2.5 u - 1
Change	+ 35	- 35	- 1	+ 1
After	4 u	1 u	2.5 u	2.5 u

(a)
25% = ²⁵₁₀₀ = ¹₄

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

In Case 2, when Ryan gives to Yoko, there is an internal transfer of money from Ryan to Yoko. 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 Yoko and Ryan have
= 4 u + 1 u
= 5 u

Amount that Yoko and Ryan each has in the end for Case 2
= 5 u ÷ 2
= 2.5 u

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

4 u - 35 = 2.5 u + 1
4 u - 2.5 u = 1 + 35
1.5 u = 36 

1 u = 36 ÷ 1.5 = 24

Amount that Ryan has
= 4 u - 35
= 4 x 24 - 35
= 96 - 35
= $61 

(b)
Amount that Yoko has
= 1 u + 35
= 1 x 24 + 35
= 24 + 35
= $59

Answer(s): (a) $61; (b) $59