Question

Following figure depicts a park where two opposite sides are parallel and

left and right ends are semi-circular in shape. It has a 7m wide track for

walking

Two friends Seema and Meena went to the park. Meena said that area of

the track is 4066m2

. Is she right? Explain.

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Answer 1

Answer:

Step-by-step explanation:

From the given figure, the track consists of 2 rectangular shaped sides and 2 semicircular shaped sides.

For the rectangular shaped side, length = 120 m and width = 7 m

For the semicircular shaped side, diameter = 70 – 2 × 7 = 70 – 14 = 56 m

So, radius of smaller semicircle = 28 m

Area of rectangular side = 120 × 7 = 840 m2

Area of semicircular side = Area of larger semicircle – Area of smaller semicircle =  

Here, R = 28 + 7 = 35 m

= 11 × 5 × 35 – 11 × 4 × 28

= 693 m2

Therefore, area of track = 2 × 840 + 2× 693

= 1680 + 1386

= 3066 m2

Thus, Meena is not right as the area is 3066 m2.