Question

A cylinder-shaped barrel has a diameter of 8 feet and a height of 7 feet. If the barrel is empty, which is closest to the minimum amount of water needed to completely fill the barrel?

Answer 1

Answer: $351.9\ ft^3$

Step-by-step explanation:

Given

The dimater of cylinder is $d=8 \ft$

The height of the cylinder is $h=7\ ft$

To fill the barrel, it must be filled with a volume equal to its volume i.e.

$\Rightarrow V=\pi r^2h\\\Rightarrow V=\pi \cdot 4^2\times 7\\\Rightarrow V=112\pi\\\Rightarrow V=351.9\ ft^3$

Thus, $351.9\ ft^3$ of water is required to completely fill the barrel.