Question

A right circular cone of height h is cut by a plane parallel to the base and at a distance h/3 from the base, then the
volumes of the resulting cone and the frustum are in the ratio
(a) 1 : 3
(b) 8 : 19
(c) 1 : 4
(d) 1 : 7

Answer 1

answer is 1:3hop it help ypu

Answer 2

Answer:

the ratio of their volume will be (b) 8 : 19

Step-by-step explanation:

Height of the original cone = h

Let radius of the original cone = r

=> volume of the original cone = πr²h/3

Height of the new cone = h - h/3 = 2h/3

=> Radius of the new cone =  2r/3

Hence volume of the new cone

= π/3 x (2r/3)² x (2h/3)

= (8/81) πr²h

So , the volume of the frustum = πr²h/3 - (8/81) πr²h

= (19/81) πr²h

Hence the ratio of their volume = (8/81) πr²h : (19/81) πr²h

= 8 : 19