Question

A cubical metal of dimensions 44 $\times$ 30 $\times$ 15 was melted and cast into a cylinder of height 28 cm. The radius of cylinder is

• A. 100
• B. 25
• C. 12
• D. 15

Answer 1

Answer: (D)

15

When shape is changed then voume will be same of those two shapes.

voluem of cylinder$=\pi r^{2}h$

volume of cube$=l\times b\times h$

$\Rightarrow 44\times 30\times 15=\pi \times 28\times r^2$

$\Rightarrow 44\times 30\times 15=\frac{22}{7}\times 28\times 2$

$\Rightarrow r^2=15\times 15$

$\Rightarrow r=15$cm.

[D].