## College Algebra 7th Edition

We know that the volume of a sphere is: $\displaystyle V=\frac{4}{3}\pi r^{3}$ We solve for $r$: $\displaystyle r=\sqrt[3]{\frac{3V}{4\pi}}$ We know that $V=750$ gallons. We convert this to cubic feet: $V=750\ gallons * 0.1337\ ft^3/gallon=100.275 ft^3$ Now we solve for $r$ in feet: $r=\sqrt[3]{\frac{3V}{4\pi}}=r=\sqrt[3]{\frac{3*100.275}{4\pi}}=2.88\ feet$