SSC CPO 2024 PYQ — Question 109

The correct answer is Option 3 i.e 406.25%.

Let the initial radius of the sphere be r

When the radius is increased by 125%, the new radius becomes:

r_new = r + 1.25r = 2.25r

The surface area of the sphere = 4πr²

New surface area = S_new = 4π × 5.0625r²

⇒ 20.25πr²

Thus,

Percentage increase = (Snew - S)/S × 100

⇒ (20.25πr² - 4πr²)/4πr² × 100

⇒ 16.25πr²/4πr² × 100

⇒ 406.25%

So, the surface area will increase by 406.25%