A cab has an average speed of 60 km / hr while going from Indore to Ujjain and has an average speed of X km / hr while returning the same distance from Ujjain to Indore. IF the average speed of the cab for the whole journey is 48 km / hr, the value of X is
1
45 km / hr
2
40 km / hr
3
36 km / hr
4
30 km / hr