Book: RS Aggarwal - Mathematics
Chapter: 18. Area of Circle, Sector and Segment
Subject: Maths - Class 10th
Q. No. 5 of Multiple Choice Questions (MCQ)
Listen NCERT Audio Books to boost your productivity and retention power by 2X.
5
On increasing the diameter of a circle by 40%, its area will be increased by
Let the radius if circle be r
Area of circle = A = πr2
Radius increases by 40%
So, New Radius r’ = r + 40/100 × r = 1.4r
New Area of circle = A’ = πr’2 = π × (1.4r)2
= 1.96πr2
Percentage increase in area = 
= 
= .96 × 100 = 96
∴ Increase in area = 96%
