Question

From a solid cylinder whose height is 4 cm and radius is 3 cm a conical conical cavity of height 4 cm and base radius 3 cm is hollowed out What is the volume of the remaining solid?

• A. $9\pi c{m}^3$
• B. $15\pi c{m}^3$
• C. $21\pi c{m}^3$
• D. $24\pi c{m}^3$

Answer 1

The correct option is D $24\pi c{m}^3$

Given Solid cylinder whose height 4 cm and radius 3 cm

Then volume of cylinder =$\pi r^{2}h=\pi \left(3{)}^2\right(4)=36\pi$sq cm

And cut conical cavity height 4 cm and radius 3 cm

Then volume =$\frac{1}{3}\pi r^{2}h=\frac{1}{3}\pi \left(3{)}^2\right(4)=12\pi$sq cm

Then remaining part =$36\pi -12\pi =24\pi c{m}^2$