Two trains 140m and 160m long run at the speed of 60kmph and 40kmph in opposite directions in parallel tracks. The time which they take to cross each other is?
Pick one
A) 5.6sec
B) 8.9sec
C) 10.8sec
D) 12.6sec
E) 15sec
Relative speed = 60+40= 
<gadget id="calculator">60+40</gadget>
<output>100</output>
100kmph * 5/18= 250/9 m/s   Distance covered in crossing each other = 140+160= 
<gadget id="calculator">140+160</gadget>
<output>300</output>
300m   Required time= 300*9/250 = 54/5= 
<gadget id="calculator">54/5</gadget>
<output>54/5 = around 10.8</output>
10.8sec   Answer is 10.8sec
<result>C</result>
Two trains 140m and 160m long run at the speed of 60kmph and 40kmph in opposite directions in parallel tracks. The time which they take to cross each other is?