Question

the distance between rajkot and jamnagar is 100 km. a motorcyclist travels at a average speed of 50 km/h. if he travels first 60 km at a uniform speed of 45 km/h. what will be his speed for the remaining journey?

Answer 1

the traveling time with an average speed of 50 km/h = 100 / 50 = 2hours

traveling time for first 60 km = 60 / 45 = 1.33 hours

motor cyclist has to cover the remaining distance 40 km in (2 - 1.33) hours 
           =  0.67 hours.

So motor cyclist's speed for remaining journey:  40 / 0.67 =  60 km / hr