Q19 of 68 Page 15

A circular pond is of diameter 17.5m. It is surrounded by a 2m wide path. Find the cost of constructing the path at the rate of ` 25 per square meter

Given,


Diameter of circular pond = 17.5m


Radius of circular pond = = 8.75m


Radius of outer circle = (radius of inner circle + width of circular path)


= 8.75+2 = 10.25m


Area of circular path = (area of outer circle – area of inner circle)


= π(R2 – r2)


= π(R+r)(R-r)


= (10.75+8.75)(10.75-8.75)


= × 19.50 × 2 = 3061.50 m2


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