Question

Find the Lateral surface area of the frustum, if the slant height is 12 cm and having radii as 15  cm and 35 cm.

(a) 1984 cm^2

(b) 1804 cm^2

(c) 1984 cm^2

(d) 1884 cm^2

I had been asked this question in homework.

Enquiry is from Surface Area & Volumes topic in division Surface Area and Volumes of Mathematics – Class 10

Answer 1

The correct choice is (d) 1884 cm^2

To explain I would say: s = 12 cm, R = 35 cm, r = 15 cm

Lateral Surface area of frustum = π(r + R)s

L = 3.14 × (15 + 35) × 12

= 1884 cm^2