Question

The length of a rectangle is halved, while its breadth is tripled. What is the percentage change in area?

Answer 1

let length be l and breadth be b
area of rectangle= l x b
let new length be l/2 and new breadth be 3b
area of new rectangle=l/2*3b=3lb/2=1/5lb
that means the new area is 1.5 times the original

Answer 2

Ar. of a rectangle= l*b,
now in the 2nd case l=l/2, and b=3b
now Ar=l/2*3b=1.5*the actual Ar.......(1.5*l*b)
therefore the % change = 1.5*100= 150%