SSC CHSL 2024 PYQ — Question 69

The correct answer is option 3 i.e. 264.

Given that

Ratio of radius (R) and height (H) of the cylinder = 6 : 7

Let radius = R and height = H

Hence, $\frac{R}{H}$ = $\frac{6}{7}$

⇒ H = $\frac{7R}{6}$

Volume of cylinder = π × R² × H

C.S.A of cylinder = 2 × π × R × H

According to the question

792 = π × R² × H

⇒ 792 = $\frac{22}{7}$ × R² × $\frac{7R}{6}$

⇒ R³ = 216

⇒ R = 6

Hence H = 7

The C.S.A. of the cylinder = 2 × π × 6 × 7 = 264

Hence, the C.S.A. of the given cylinder is 264 cm² .