Question

The radius and the slant height of a cone are 5 cm and 10cm respectively . What is its curved surface area ?


314 cm²


157 cm²


78.5cm²


100 cm²

6.​

Answer 1

Given :

• Radius of Cone = 5cm.
• Slant Height of Cone = 10cm

To Find :

• Curved Surface Area of Cone

Solution :

$\longmapsto\tt{Radius(r)=5cm}$

$\longmapsto\tt{Slant\:Height(h)=10cm}$

Using Formula :

$\longmapsto\tt\boxed{C.S.A\:of\:Cone=\pi{rl}}$

Putting Values :

$\longmapsto\tt{\dfrac{22}{7}\times{5}\times{10}}$

$\longmapsto\tt{\dfrac{220\times{5}}{7}}$

$\longmapsto\tt{\cancel\dfrac{1100}{7}}$

$\longmapsto\tt\bold{157.1{cm}^{2}\:(Approx.)}$

So , The C.S.A of Cone is 157.1 cm²..

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• C.S.A of Cone = πrl
• T.S.A of Cone = πrl(l+r)
• Volume of Cone = 1/3 πr²h

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