Question

a train running at average speed of 48km/hr perform a journey  at 6hrs 30 min how long would the same  journey take it after crossing 180kms the speed was reduced to 33km/hr

Answer 1

First of all we will find the distance So distance = speed x time = 48x6 1/2 = 48x13/2 = 24x 13 = 312 kms now case second total distance = 312 kms and speed = 48km/hr for first 180 kms Time = d/ s = 180 / 48 = 90/24=45/12=15/4 now time taken in remaining = 132 kms Now time = d/s = 132/33 = 12 / 3 = 4 hrs Total time taken = 4 + 15/4 = 31/4 hrs