A man is running at the speed of 54 km/h. What is the time taken by man to cover one round of circular garden of radius 70 m?

29.33 sec

1 round of circular garden = 2πr

                                         = 2 × \(\frac{22}{7}\) × 70

                                         = 440 m

Speed of man = 54 × \(\frac{5}{18}\) = 15 m/sec

Time taken to cover this distance = \(\frac{distance}{speed}\)

                                                     = \(\frac{440}{15}\)

                                                     = 29.33 seconds