19. A train 130 metres long and travelling at 45 km/hr can cross a bridge in 30 seconds. Find the length of the bridge.

Answer:

245 m.  

Explanation:

Speed =		45 x	5	m/sec	=		25	m/sec.
			18				2

Time = 30 sec.

Let the length of bridge be x metres.

Then,	130 + x	=	25
	30		2

 2(130 + x) = 750

 x = 245 m.