Question

A path of width 5 m is built around the circular park of radius 15 m. Find the area
of the path.

​

Answer 1

Answer:

O is the centre of a circular park of radius OA=105 m with a concentric surrounding circular road of width AB=21 m

To find the area of the road, first we need to find area of the park and then subtract the area of park from total area including road.

Let's find area of a park.

Park forms a circle with radius(r)=105 m

∴ Area of the park =πr

2

=π(105)

2

The outer circle represents total area which includes park and road with radius(R)=105+21=126

∴ Total area =πR

2

=π(126)

2

Thus, area of the road = Total area − Area of park

=π(126)

2

−π(105)

2

=π(126

2

−105

2

)=4851π=15246 m

2

Hence, area of road =15246 m

2

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