Question

Find the surface area of a frustum of cone given below: (Use = $\pi$ 3.14)

• A. 954.6856 m${}^2$
• B. 654.6856 m${}^2$
• C. 854.6856 m${}^2$
• D. 754.6856 m${}^2$

Answer 1

Answer: (A)

954.6856 m${}^2$

Surface area of a frustum of cone = $\pi$(r + R)s + $\pi$r${}^2$ + $\pi$R${}^2$

D = 5 m, d = 0.1 m, s = 20 m

Diameter = radius/2

Radius, R = 10 m, r = 0.2 m

$=\pi (0.2+10)20+\pi {0.2}^2+\pi {10}^2$

$=3.14(204+0.04+100)$

$=3.14\left(304.04\right)$

$=954.6856m^2$