Two trains are running in opposite directions with the same speed. If the length of each train is 300 m and they cross each other in 12 sec, then the speed of each train is?
Answers:	A) 22	B) 77	C) 36	D) 90	E) 21
Let the speed of each train be x m/sec.   Then, relative speed of the two trains = 2x m/sec.   So, 2x = (300 + 300)/12 =&gt; x = 25   Speed of each train = 10 m/sec.   = 25 * 18/5 =- 90 km/hr.   Answer: 90
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Two trains are running in opposite directions with the same speed. If the length of each train is 300 m and they cross each other in 12 sec, then the speed of each train is?