Shiyun buys a windbreaker, a jacket, a blazer and a blouse. The average cost of these items is $44. The total cost of the blazer and the blouse is ⁵₆ of the total cost of the windbreaker and the jacket. If the windbreaker costs $15.80 and the blouse costs $17.70, find the difference in cost between the jacket and the blazer.
Total cost of the 4 items
= 4 x 44
= $176

Total cost of the blazer and the blouse = 5 u
Total cost of the windbreaker and the jacket = 6 u

Total cost of the 4 items
= 5 u + 6 u
= 11 u

11 u = 176

1 u = 176 ÷ 11 = 16

Total cost of the blazer and the blouse
= 5 u
= 5 x 16
= $80

Cost of the blazer
= 80 - 17.70
= $62.30

Total cost of the windbreaker and the jacket
= 6 u
= 6 x 16
= $96

Cost of the jacket
= 96 - 15.80
= $80.20

Difference in cost between the jacket and the blazer
= 80.20 - 62.30
= $17.90

Answer(s): $17.90