Question

A circular playground has a area of 616 sq.M what time will it take for a runner to run around the circular ground at the speed of 22 km/h

Answer 1

hey
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area = 616
πr^2 =616
22/7r^2=616
r^2=616×7/22
r^2=28×7
r=√196
r=14

distance covered = circumference
2πr = 2×22/7×14=88

speed = distance /time
speed×time = distance
22×1000/60×60×time =88
6.11 × time =88
time =88/6.11
time = 88×100/611
time = 14.4 s


hope helped
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Answer 2

Heya !

Here's your answer !!

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Area of a circular playground = 616 m²

Formula for area of circle = πr²

{ Where r = radius and π = 22/7 }

=> 616 = πr²

=> r² = 616 × 7/22

=> r² = 28 × 7

=> r = √196 = 14 m

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Circumference of circle = 2πr

=> 2 × 22/7 × 14

=> 44 × 2 = 88 m

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Speed of the runner = 22 km/h

Therefore, time taken to run around the circular ground = ?

Converting km/h into m/s because distance is Given in metres

Therefore,

For converting it into m/s :

The Equation would be

=> ( 22×1000 )/( 60 × 60 )

Because 1 km = 1000 m

1 hour = ( 60 × 60 ) seconds

Speed = 6.11 m/s


Time Taken = Distance/Speed

=> 88/6.1

=> 14.42 seconds ANS

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Thanks !!