Ethan had $300 and Henry had $152 at first. Each of them bought an identical blouse and an identical sweater from the same shop. The sweater cost 5 times as much as the blouse. In the end, Ethan had 3 times as much money as Henry. What was the cost of the blouse?

	Ethan	Henry	Difference
Before	$300	$152	$148
Change	- 1 blouse - 1 sweater	- 1 blouse - 1 sweater
After	3 u	1 u	2 u

Since Ethan and Henry bought the same items, the difference  in their amounts remains the same.

Difference in the amounts that they had
= 3 u - 1 u
= 2 u

2 u = 300 - 152
2 u = 148

1 u = 148 ÷ 2 = 74

Amount that Henry had in the end
= 1 u
= $74

Cost of 1 blouse and 1 sweater
= 152 - 1 u
= 152 - 74
= $78

The sweater cost 5 times as much as the blouse.

Cost of 1 blouse = 1 p
Cost of 1 sweater = 5 p

Total cost of 1 blouse and 1 sweater
= 1 p + 5 p
= 6 p

6 p = 78

1 p = 78 ÷ 6 = 13

Cost of the blouse
= 1 p
= $13

Answer(s): $13