Question

A circular pond is to be surrounded by a gravel path. Use the diagram to find the square feet of gravel needed if we know the pond has a radius of 200 ft and the radius of the whole space is 250 ft?

Answer 1

Area of the whole space:
A 1 = r² π = 250² π = 62,500 π = 62,500 · 3.14 = 196,250 ft²
The circular pond area:
A 2 = 200² π = 40,000 π = 40,000 · 3.14 = 125,600 ft²
The area of gravel path:
196,250 - 125,600 = 70,650 ft²