Two trains are running in opposite directions with the same speed. If the length of each train is 420 m and they cross each other in 12 sec, then the speed of each train is?  Choose the correct choice from the following options
A) 11  B) 26  C) 126  D) 99  E) 27
Let the speed of each train be x m/sec.   Then, relative speed of the two trains = 2x m/sec.   So, 2x = (420 + 420)/12 =&gt; x = 35   Speed of each train = 10 m/sec.   = 35 * 18/5= 
<gadget id="calculator">35 * 18/5</gadget>
<output>126</output>
126 km/hr.   Answer: 126
<result>C</result>
Two trains are running in opposite directions with the same speed. If the length of each train is 420 m and they cross each other in 12 sec, then the speed of each train is?