Question

Curved surface area of a hemisphere is equal to 2772 cm^2, what is its volume? (Take π = \(\frac{22}{7}\))

(a) 19464 cm^3

(b) 19404 cm^3

(c) 19427 cm^3

(d) 19425 cm^3

The question was asked during an internship interview.

This interesting question is from Volume of a Sphere topic in chapter Surface Areas and Volumes of Mathematics – Class 9

Answer 1

Correct option is (b) 19404 cm^3

The explanation: We know that curved surface area of a hemisphere is equal to 2πr^2.

2πr^2 = 2772

r^2 = \(\frac{2772*7}{2*22}\) = 441

Therefore, r = 21cm

Now, we know that volume of a hemisphere is equal to \(\frac{2}{3}\) πr^3.

Hence, V = \(\frac{2}{3}\) πr^3

= \(\frac{2*22*21*21*21}{3*7}\)

= 19404 cm^3.