Question

The perimeter of the base of a right circular cone is 8 cm
If the height of the cone is 21 cm, then its volume is​

Answer 1

Step-by-step explanation:

Perimeter of the base of the cone is equal to the circumference of the base.

Formula of circumference = 2πr

Therefore, 8 =2πr

4 = πr

r = 14/11cm

(leave the radius in fraction as it may cancel out later)

Now h = 21cm (given)

Volume = 1/3 πr²h

= (196×2)/11

= 392/11

=35.6363•cm³(recurring)

Answer 2

Answer:

1/2 base×height

1/2 8×21

1/2×168

1×168/2

84

I hope is my answer is right