Question

A ball has a diameter of 9 in. It consists of 2 parts. The inside is a spherical core with a diameter of 6 in. Surrounding the core is a layer of polyurethane.

What is the volume of the polyurethane?

Use 3.14 to approximate pi and express your answer in hundredths.

in3

Answer 1

Lads, answer is 268.47 Just took the Quiz.

Answer 2

This question is basically just asking you to take the volume of the entire ball and subtract the volume of the core (the part that's not polyurethane) to find the volume of the polyurethane.

The formula for the volume of a sphere is
`(4)/(3) \pi r^(3)` where r = the radius. First, let's find the volume of the whole sphere.


`V=(4)/(3) \pi 9^(3)`


`V=(4)/(3) \pi 729`


`V=\pi 972`

Now let's find the volume of the inner core.


`V=(4)/(3) \pi 6^(3)`


`V=(4)/(3) \pi 216`


`V=\pi 288`

972π - 288π = 684π

Use 3.14 for π and we get 684*3.14 = 2147.76 in³.