Two trains 170 m and 160 m long run at the speed of 60 km/hr and 40 km/hr respectively in opposite directions on parallel tracks. The time which they take to cross each other is?	Choose the correct choice from the following.
A) 10.7
B) 10.9
C) 10.2
D) 10.88
E) 11.88
Relative speed = 60 + 40= 
<gadget id="calculator">60 + 40</gadget>
<output>100</output>
100 km/hr.= 100 * 5/18 = 250/9 m/sec.   Distance covered in crossing each other = 170 + 160= 
<gadget id="calculator">170 + 160</gadget>
<output>330</output>
330 m.   Required time= 330 * 9/250= 
<gadget id="calculator">330 * 9/250</gadget>
<output>297/25 = around 11.88</output>
11.88 sec.   Answer:11.88
<result>E</result>
Two trains 170 m and 160 m long run at the speed of 60 km/hr and 40 km/hr respectively in opposite directions on parallel tracks. The time which they take to cross each other is?