**Question: **A jogging path of width 4ft goes around a circular play area for
children. The diameter of the play area is 90 ft. The administration is
considering relaying the tiles in jogging path. if the cost of laying is
quoted as 15 dollars per sq.ft, find the total cost for relaying tiles
on the jogging path.

** Solution: **

The area of the path can be calculated using annulus area formula

where R = radius of the outer circle = 45 + 4 = 49 ft and r = radius of the play area = 45 ft

Area of the jogging path = π(R^{2} - r^{2})

= π(49^{2} - 45^{2}) = 1181.24 sq ft.

Cost of relaying per sq ft = 15 dollars

Total cost of relaying tiles on jogging path = 1181.24 x 15 = 17,718.60 dollars.