Question

Find the volume (in cubic feet) of a cylindrical column with a diameter of 6 feet and a height of 28 feet. (Round your answer to one decimal place.)

Answer 1

`791.7\:\mathrm{ft^3}`

Explanation:

The volume of a cylinder with radius
`r` and height
`h` is given by
`A_(cyl)=r^2h\pi`.

By definition, all radii of a circle are exactly half of all diameters of the circle. Therefore, if the diameter of the circular base of the cylinder is 6 feet, the radius of it must be
`6/ 2=3\text{ feet}`.

Now we can substitute
`r=3` and
`h=28` into our formula
`A_(cyl)=r^2h\pi`:

`A=3^2\cdot 28\cdot \pi,\\A=9\cdot28\cdot \pi,\\A=791.681348705\approx \boxed{791.7\:\mathrm{ft^3}}`