What is the % change in the area of a rectangle when its length increases by 30% and its width decreases by30%? Choose the correct choice.
A) 0 %
B) 20 % increase
C) 20 % decrease
D) 9 % decrease
E) insufficient data

Rationale: "( 13 / 10 ) * ( 7 / 10 ) = 91 / 100 of original area 91 / 100 is a 9 % decrease from 100 / 100 - > d"
Answer: D