Glen and Owen had $102 and $78 respectively. Each of them bought a skirt and a shirt at the same price. The cost of the skirt was 3 times as much as the shirt. In the end, Glen had 5 times as much money as Owen. What was the difference between the cost of the shirt and the skirt?

	Glen	Owen	Difference
Before	$102	$78	$24
Change	- 4 p	- 4 p
After	5 u	1 u	4 u

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

5 u - 1 u = 102 - 78
4 u = 24

1 u = 24 ÷ 4 = 6

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

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

4 p = 78 - 6
4 p = 72

1 p = 72 ÷ 4 = 18

Difference in the cost between the skirt and the shirt
= 3 p - 1 p
= 2 p
= 2 x 18
= $36

Answer(s): $36