Question

A cylindrical solid with base radius $5$ cm and height $8$ cm is melted down to form $12$ identical cones with base radii $4$ cm. Calculate the height of each cone.

• A. $\frac{25}{24}cm$
• B. $\frac{5}{24}cm$
• C. $\frac{55}{24}cm$
• D. None of these

Answer 1

The correct option is D None of these

Vol.of cyl $=12\times$ Vol.of cone

$\Rightarrow \pi \left(5^2\right)\times 8=12\times \frac{\pi }{3}\times 4^2\times h$

$\Rightarrow h=\frac{25}{8}cm$