# SAT rectangle problem

• May 30th 2012, 01:14 PM
Mat724
SAT rectangle problem
If the length of a rectangle is increased by 30% and the width of the same rectangle is decreased by 30%, what is the effect on the area of a rectangle?
• May 30th 2012, 01:41 PM
britmath
Re: SAT rectangle problem
Obviously the area of a rectangle with length L and width W is L*W, so, you want to think about how you might modify this product to reflect the fact that L is 30% larger and W is 30% smaller; if you then write this new product down, hopefully you'll be able to see how the area is modified.
• May 31st 2012, 06:39 AM
Mat724
Re: SAT rectangle problem
i got no change somehow... but that is wrong... This is a level 5 question on the SAT practice test. No wonder its pretty difficult
• May 31st 2012, 07:49 AM
skeeter
Re: SAT rectangle problem
Quote:

Originally Posted by Mat724
If the length of a rectangle is increased by 30% and the width of the same rectangle is decreased by 30%, what is the effect on the area of a rectangle?

original rectangle ... $A_1 = LW$

modified rectangle ... $A_2 = (1.3L)(0.7W) = 0.91LW = 0.91A_1$