Two trains A and B star from station X and Y toward Y and X respectively. After passing each other, they take 4 hours 48 minutes and 3 hour 20 minutes to reach Y and X respectively. If train A is moving at 45 km/hr. then the speed of train B is:
A. 60 km/hr
B. 54 km/hr
C. 64.8 km/hr
D. 37.5 km/hr
ANSWER : B.