Question

If the radius of the base of a cylinder is doubled, keeping the height same, find the ratio of the volume of the new cylinder to that of the original cylinder.

• A. 2 :1
• B. 3:2
• C. 3:1
• D. 4:1

Answer 1

The correct option is D

4:1

Let the radius of the original cylinder = r

Hence the radius of the new cylinder = 2r

$\frac{\text{Volume of the new cylinder}}{\text{Volume of the original cylinder}}=\frac{\text{/}\pi (2r{)}^{2}h}{\text{/}\pi r^{2}h}=\frac{4}{1}$