A solid metal sphere of radius 9 cm is melted and recast into a solid cylinder of radius 6 cm. What is the height of the cylinder?

Explanation

1. 01

   Volumes are equal: $\frac{4}{3}\pi \times 9^3 = \pi \times 6^2 \times h$.

2. 02

   π cancels: $972 = 36h$, so $h = 27$ cm. (No value of π is needed.)