if the volume of a sphere is 250 inches cubic, then what is the radius? About how many inches?
Vsphere = (4/3) * pi * radius^3 .... so ....
250 = (4/3) * pi * radius^3 divide both sides by (4/3) pi
250 / [ (4/3) pi ] = radius^3 take the cube root of each side
∛ [ 250 / (4/3 pi) ] = r ≈ 3.9 inches