# If the Height and Radius of a Cone of Volume V Are Doubled, Then the Volume of the Cone, is - Mathematics

MCQ

If the height and radius of a cone of volume V are doubled, then the volume of the cone, is

•  3 V

•  4 V

• V

• V

#### Solution

The formula of the volume of a cone with base radius ‘r’ and vertical height ‘h’ is given as

Volume of cone =  1/3 pi r^2h= V

Since it is given that the radius and height are doubled we have the radius as ‘2r’ and the vertical height as ‘2h

So now,

Volume of modified cone =1/3 pi(2r)^2 (2h)

=8/3pi r^2 h

= 8V

Is there an error in this question or solution?

#### APPEARS IN

RD Sharma Mathematics for Class 9
Chapter 20 Surface Areas and Volume of A Right Circular Cone
Q 8 | Page 25