Question

The C.S.A of cone is 1159 cm” and the area of its base is 254 cm", then its volume is!
A) 3394 cm B) 33942cm 9133942cm D) 33942.com"
Chaitanya School
No.1 School i
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Answer 1

Solution:-

Given:-

• The C.S.A of cone is 1159 cm².
• Area of its base is 254 cm².

To Find:-

• Volume of Cone = ?

Find:-

Area of its base is 254 cm²

=) πr² = 254

=) r² = 254 × 7/22

=) r² = 80.81

=) r = √ 80.81

=) r = 8.98 cm

• Radius of Cone = 8.98cm

Now,

C.S.A. of Cone = 1159

=) πrl = 1159

=) l = 1159 × (7/22) × (1/8.98)

=) l = 41.06 cm

• Slant Height of the Cone = 41.06 cm

Now,

( Slant Height)² = Height ² + Radius ²

L² = H² + R²

=) ( 41.06)² = H² + ( 8.98 )²

=) 1685.92 - 80.64 = H²

=) H = √1605.28

=) H = 40.06 cm

• Height of the Cone = 40.06 cm

Now,

Volume of Cone = 1/3 πr²h

=) Volume = 1/3 × 22/7 × (8.98)² × (40.06)

=) Volume = 3,391.40 cm³

Hence,

Volume of Cone is 3391.40 cm³.