Roshel buys a blazer, a dress, a windbreaker and a vest. The average cost of these items is $35. The total cost of the windbreaker and the vest is ²₅ of the total cost of the blazer and the dress. If the blazer costs $14.50 and the vest costs $6.60, find the difference in cost between the dress and the windbreaker.
Total cost of the 4 items
= 4 x 35
= $140

Total cost of the windbreaker and the vest = 2 u
Total cost of the blazer and the dress = 5 u

Total cost of the 4 items
= 2 u + 5 u
= 7 u

7 u = 140

1 u = 140 ÷ 7 = 20

Total cost of the windbreaker and the vest
= 2 u
= 2 x 20
= $40

Cost of the windbreaker
= 40 - 6.60
= $33.40

Total cost of the blazer and the dress
= 5 u
= 5 x 20
= $100

Cost of the dress
= 100 - 14.50
= $85.50

Difference in cost between the dress and the windbreaker
= 85.50 - 33.40
= $52.10

Answer(s): $52.10