Question

the radius and height of a cone are in the ratio 4:3 the area of its base 154cmsq.. . find its curved surface area.

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Answer 1

Answer:

We have given the ratio of radius and height 4 : 3

Say Radius = 4x

Height = 3x

Slant Height = root [(4x)2 +(3x)2 ]=5x { as it goes to Pythagorean Theorem}

as we know, Area of Base = pie X radius2 =>154=22/7 X 16x2

so solving the eq we get x=1.75cm

Radius=7 , Height =5.25cm, Slant Height =8.75cm

So csa or Curved Surface Area = pie X radius x slant height = 22/7 X 7 X 8.75 x=192.5cm2 (ans)