Question

Suppose the sphere below with radius r has a volume equal to45 units. Find the volume of the sphere with twice the radius.-27-A. 90 units 3B. 360 units3C. 180 units3D. 450 units2

Answer 1

The volume of the given sphere is 45 cubic units

$\frac{4}{3}\pi\times r^3=45^{}$

Now replce r by 2r so that:-

$\begin{gathered} \frac{4}{3}\pi\times(2r)^3=\frac{4}{3}\pi\times8\times r^3 \\ =8\times\frac{4}{3}\pi\times r^3 \\ =8\times45 \\ =360 \end{gathered}$

So the volume of the sphere twice the radius of first sphere is 360 cubic units.

Hence the correct option is (B).