Question

A concrete walk of uniform width is to be built around a circular pool. The radius of the pool is 12 meters, and enough concrete is available to cover 52(pie) square meters. If all the concrete is to be use, how wide should the walk be?

Answer 1

The area of that walkway will be pi*(12+w)^2 - pi*12^2 = 52pi
The pi's cancel so you get (12 + w)^2 - 144 = 52.
Solve for w