Glen and Daniel had $128 and $113 respectively. Each of them bought a shirt and a skirt at the same price. The cost of the shirt was 5 times as much as the skirt. In the end, Glen had 4 times as much money as Daniel. What was the difference between the cost of the skirt and the shirt?

	Glen	Daniel	Difference
Before	$128	$113	$15
Change	- 6 p	- 6 p
After	4 u	1 u	3 u

Since Glen and Daniel 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 = 128 - 113
3 u = 15

1 u = 15 ÷ 3 = 5

Cost of 1 shirt = 5 p
Cost of 1 skirt = 1 p

Total cost of 1 shirt and 1 skirt
= 5 p + 1 p
= 6 p

6 p = 113 - 5
6 p = 108

1 p = 108 ÷ 6 = 18

Difference in the cost between the shirt and the skirt
= 5 p - 1 p
= 4 p
= 4 x 18
= $72

Answer(s): $72