The ratio of the radius and height of a cylinder is 3 : 2. The radius

1.	The ratio of the radius and height of a cylinder is 3 : 2. The radius is 21 cm, then Lateral Surface Area (LSA) = ……… cm2A) 2043 B) 1949 C) 1848 D) 1948
Answer» Correct option is: C) 1848 Given that \(\frac rh = \frac 32 \) and r = 21 cm \(\therefore\) h = \(\frac 23 r = \frac 23 \times 21 = 14 \, cm\) \(\therefore\) LSA of cylinder = \(2 \pi rh\) = \(2 \times \frac {22}7 \times 21 \times 14 = 44 \times 42= 1848 \, cm^2\) Hence, the lateral surface area of cylinder is 1848 \(cm^2\) Correct option is: C) 1848

The ratio of the radius and height of a cylinder is 3 : 2. The radius is 21 cm, then Lateral Surface Area (LSA) = ……… cm2A) 2043 B) 1949 C) 1848 D) 1948

Answer»

Correct option is: C) 1848

Given that \(\frac rh = \frac 32 \) and r = 21 cm

\(\therefore\) h = \(\frac 23 r = \frac 23 \times 21 = 14 \, cm\)

\(\therefore\) LSA of cylinder = \(2 \pi rh\)

= \(2 \times \frac {22}7 \times 21 \times 14 = 44 \times 42= 1848 \, cm^2\)

Hence, the lateral surface area of cylinder is 1848 \(cm^2\)

Correct option is: C) 1848