Carcass wrote:
A boy is photocopying a rectangular poster. He sets the copier to increase the length of the poster by 30% and the width of the poster by 40%. The increase in the area of the poster is equal to x%. What is the value of x?
68
70
75
78
82
Let's say the ORIGINAL poster has length 10 and width 10
So the original area = (10)(10) =
100 square units
Since length is increased by 30%, and the width is increased by 40%, the ENLARGED poster has length 13 and width 14.
So the ENLARGED area = (13)(14) =
182 square units
Percent increase = (100)(new - old)/old = (100)(
182 -
100)/
100= (100)(82)/100
= 82%
Answer: E