SSC GD 2019 PYQ — Question 67

The correct answer is option 4 i.e. 32.25%

If diameter of circle in  increases by 15% then radius will also be increased by 15% 

Let radius of circle be x then the new

radius will be x +(15% of x) = 1.15x

initial area = πx²

New area = π × (1.15x)² = 1.3225πx²

Percent increase = (1.3225πx² -  πx²) × 100/ πx²

Percent increase = 0.3225 πx² × 100/ πx² 

Percent increase = 32.25%