Carl buys a shirt, a jumpsuit and a blazer. The average cost of these items is $84. The cost of the blazer is four times the total cost of the shirt and the jumpsuit. If the shirt costs $15, find the difference in cost between the jumpsuit and the blazer.
Total cost of the 3 items
= 3 x 84
= $252

Total cost of the shirt and the jumpsuit = 1 u
Cost of the blazer = 4 u

Total cost of the 3 items 
= 1 u + 4 u
= 5 u

5 u = 252 

1 u = 252 ÷ 5 = 50.40

Total cost of the shirt and the jumpsuit = $50.40

Cost of the jumpsuit 
= 50.40 - 15
= $35.40

Cost of the blazer
= 4 u
= 4 x 50.40
= $201.60

Difference in cost between the jumpsuit and the blazer
= 201.60 - 35.40
= $166.20

Answer(s): $166.20