Question

A spherical helium balloon has a diameter of 30 cm. How much helium is needed to fill the balloon, in cubic centimeters? Round your answer to the nearest centimeter

Answer 1

if the diameter is 30, then the radius is half that, or 15

$\bf \textit{volume of a sphere}\\\\ V=\cfrac{4\pi r^3}{3}\quad \begin{cases} r=radius\\ -----\\ r=15 \end{cases}\implies V=\cfrac{4\pi 15^3}{3}$