Mathematics

Problem

A hollow cylindrical iron pipe is

2.1\,\text{m}

long. Its outer diameter is

10\,\text{cm}

and the thickness of the metal is

1\,\text{cm}

. Find the mass of the pipe if the density of iron is

8\,\text{g/cm}^{3}

. (Use

\pi = \frac{22}{7}

)