If the length of a rectangle is halved and its breadth is tripled, what is the percentage change in its area?

Let original length = 10
original breadth = 10
Then, original area = 10 × 10 = 100
Length is halved
⇒ New length = 10/2
= 5
breadth is tripled.
⇒ New breadth = 10 × 3
= 30
New area = 5 × 30
= 150
Increase in area
= new area - original area
= 150 - 100
= 50
Percentage increase in area
= {(increase in area/original area) × 100}%
= {(50/100) × 100}%
= 50%.