Two station L and M are 720 km apart from each other. A train leaves from L to M and simultaneously another train leaves from M to L. Both trains meet after 24 hours. If the speed of the first train is 10 km/hr more than the second train, then what is the speed of the slower train?

A

20 km/hr

B

16 km/hr

C

14 km/hr

D

10 km/hr