Tommy and Jenson had $136 and $115 respectively. Each of them bought a shirt and a skirt at the same price. The cost of the shirt was 3 times as much as the skirt. In the end, Tommy had 4 times as much money as Jenson. What was the difference between the cost of the skirt and the shirt?

	Tommy	Jenson	Difference
Before	$136	$115	$21
Change	- 4 p	- 4 p
After	4 u	1 u	3 u

Since Tommy and Jenson bought the same items at the same price, the difference in the amounts they had remains unchanged at first and in the end.

4 u - 1 u = 136 - 115
3 u = 21

1 u = 21 ÷ 3 = 7

Cost of 1 shirt = 3 p
Cost of 1 skirt = 1 p

Total cost of 1 shirt and 1 skirt
= 3 p + 1 p
= 4 p

4 p = 115 - 7
4 p = 108

1 p = 108 ÷ 4 = 27

Difference in the cost between the shirt and the skirt
= 3 p - 1 p
= 2 p
= 2 x 27
= $54

Answer(s): $54