Question

A man starts to run along a particular direction with a speed of 54 km./hours. After running upto a distance of 100 m, he increases his speed by 50 % of the initial speed, and runs upto 200 m. Total time taken by the man will be

Answer 1

Total Distance = 200 m

Speed = 15 m/s

Time taken to cover 100 m , t1 = 100/15 = 6.66 s

Now, New Speed = 15 + 15/2 = 45/2 m/s

so, time taken to cover 100 m now, t2 = 100*2/45 = 4.44 s

Hence total time taken = t1 + t2 = 4.44 + 6.66  = 11.1 seconds