Q13 of 47 Page 1

From a solid cylinder whose height is 8 cm and radius 6 cm, a conical cavity of same height and same base radius is hollowed out. Find the total surface area of the remaining solid. (Take π = 3.14)

Height (h) = 8 cm

Radius (r) = 6 cm


Slant height (l) =


⇒ Slant height (l) = 10 cm


Lateral surface Area of cone (A) = π × r × l = 188.4 cm2


Lateral surface Area of cylinder(a) = 2π × r × h = 301.44 cm2


Base Area (A’) = π × r2 = 113.04 cm2


Total surface area of the remaining solid = (A + a + A’)


Answer: Total surface area of the remaining solid is 602.88 cm2


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