Q7 of 37 Page 13

Rajeev walks around a circular park of area 88704 sq. m How long will he take to walk 10 rounds at the speed of 4.5 km per hour?

Area of circular park = 88704 m2


and Area of circle = πr2 = 88704




⇒ r2 = 28224


⇒ r = √28224


⇒ r = 168m


[taking positive root, because radius can’t be negative]


Perimeter of circle = 2πr



= 1056 m


= 1.056 km


So, total distance after 10 rounds = 1.056 × 10 = 10.56km


Now, we know that



Here, Speed = 4.5 km/hr


Distance = 10.56 km


Putting value in formula, we get




= 2.34 hour


= 2 hours 20 minutes 24 seconds


Hence, Rajeev will take 2 hours 20 minutes and 24 seconds to walk 10 rounds.


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