Wesley had $324 and Peter had $111 at first. Each of them bought an identical hoodie and an identical skirt from the same shop. The skirt cost 4 times as much as the hoodie. In the end, Wesley had 4 times as much money as Peter. What was the cost of the hoodie?

	Wesley	Peter	Difference
Before	$324	$111	$213
Change	- 1 hoodie - 1 skirt	- 1 hoodie - 1 skirt
After	4 u	1 u	3 u

Since Wesley and Peter bought the same items, the difference  in their amounts remains the same.

Difference in the amounts that they had
= 4 u - 1 u
= 3 u

3 u = 324 - 111
3 u = 213

1 u = 213 ÷ 3 = 71

Amount that Peter had in the end
= 1 u
= $71

Cost of 1 hoodie and 1 skirt
= 111 - 1 u
= 111 - 71
= $40

The skirt cost 4 times as much as the hoodie.

Cost of 1 hoodie = 1 p
Cost of 1 skirt = 4 p

Total cost of 1 hoodie and 1 skirt
= 1 p + 4 p
= 5 p

5 p = 40

1 p = 40 ÷ 5 = 8

Cost of the hoodie
= 1 p
= $8

Answer(s): $8