Problem P. 4214. (January 2010)
P. 4214. A freight train, undergoing uniform motion, passes the semaphore next to the rails in 4 seconds. Then it passes a 40m long train, which moves with the same speed as the freight train but into the opposite direction, also in 4 seconds. What is the speed of the freight train in km/h?
(3 pont)
Deadline expired on 10 February 2010.
Sorry, the solution is available only in Hungarian. Google translation
Megoldás. A vonat hossza 40 m, sebessége 36 km/h.
Statistics:
>175 students sent a solution.  
3 points:  134 students. 
2 points:  14 students. 
1 point:  14 students. 
0 point:  10 students. 
Unfair, not evaluated:  3 solutions. 
