If Erika gives Julian $28, the amount of money she has will be 40% of his. If Julian gives Erika $11, he will have the same amount of money as her. How much money did each of them have?
(a) Julian
(b) Erika

	Case 1		Case 2
	Julian	Erika	Julian	Erika
Before	5 u - 28	2 u + 28	3.5 u + 11	3.5 u - 11
Change	+ 28	- 28	- 11	+ 11
After	5 u	2 u	3.5 u	3.5 u

(a)
40% = ⁴⁰₁₀₀ = ²₅

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

In Case 2, when Julian gives to Erika, there is an internal transfer of money from Julian to Erika. 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 Erika and Julian have
= 5 u + 2 u
= 7 u

Amount that Erika and Julian each has in the end for Case 2
= 7 u ÷ 2
= 3.5 u

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

5 u - 28 = 3.5 u + 11
5 u - 3.5 u = 11 + 28
1.5 u = 39 

1 u = 39 ÷ 1.5 = 26

Amount that Julian has
= 5 u - 28
= 5 x 26 - 28
= 130 - 28
= $102 

(b)
Amount that Erika has
= 2 u + 28
= 2 x 26 + 28
= 52 + 28
= $80

Answer(s): (a) $102; (b) $80