Q21 of 68 Page 15

A path of width 3.5m runs around a semi-circular grassy plot whose perimeter is 72m. find the area of the path.

Given,


Perimeter of semi-circle = 72m


Width of path around it = 3.5m


Perimeter of semi-circle = πr+2r


= r +2r = 72


= 22r+14r = 72×7


r = = 14cm


Radius including the width of path(R) = r+3.5 = 14+3.5 = 17.5m


So, area of path =




= 173.25m2


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