# Volume of a right circular cone is 78848 centimetre cube its diameter is 56 centimetre find total surface area

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by zeb1

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by zeb1

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volume (v)=78848cm³

diameter=56cm

so radius (r)= 28cm

now

volume of a cone=πr²h

=>78848=22/7*28*28*h

=>h=32

now

TSA=πr(r+l)

=22/7*28(28+√32²+28²

=3741.811cm²

radius = 28cm

Now, 1/3Πr²h = 78848

1/3 x 22/7 x 28 x 28 x h = 78848

22 x 4 x 28 x h = 78848 x 3

2464 x h = 236544

h = 96cm

Now, T.S.A of Cone = Πrl + Πr²

since, l = sant height

∴ height² + radius² = l²

96² + 28² = l²

9216 + 784 = l²

10000 = l²

∴ l = 100cm

Now, TSA = 22/7 x 28 x 100 + 22/7 x 28 x 28

= 800+2464

= 3264cm²

TSA of Cone = 3264cm²