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Question
Mukesh walks around a circular track of radius 14 m with a speed of 4 km/hr. If he takes 20 rounds of the track, for how long does he walk?
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Solution
Radius of the circular track = 14 m
Circumference of the circular track = 2πr
= `2 xx 22/7 xx 14`
= 44 × 2
= 88 m
Total distance cover in 20 rounds = 88 × 20 = 1760 m
Speed of Mukesh on the circular track = 4 km/h
= `(4 xx 1000)/60`
= `(2 xx 100)/3`
= `200/3` m/min
Time taken by Mukesh = `1760/(200/3)`
= `(1760 xx 3)/200`
= `(176 xx 3)/20`
= 26.4 min
26.4 min = 26 min and 24 s
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