How many spherical bullets each of 5cm in diameter can be cast from a rectangular block of metal 11dm\times 1m\times 5dm?
How many spherical bullets each of 5cm in diameter can be cast from a rectangular block of metal 11dm\times 1m\times 5dm?

It is given that,

A metallic block of dimension 11dm\times 1m\times 5dm

The diameter of each bullet =5cm

As, we know that

Formula of volume of the sphere =4\pi {{r}^{3}}

As, we know that, 1dm={{10}^{-1}}m=0.1m

The volume of the rectangular block =1.1\times 1\times 0.5=0.55{{m}^{3}}

Radius of the bullet =5/2=2.5cm

Assume the number of bullets made from the rectangular block be n.

Now from the question,

The volume of the rectangular block = sum of the volumes of the n spherical bullets

0.55=n\times 43\pi {{\left( 2.5 \right)}^{3}}

Solving for n, we have

n=8400

Hence, 8400 can be cast from the rectangular block of metal.