A train 150 m long passes a km stone in 15 seconds and another train of the same length travelling in opposite direction in 8 seconds.The speed of the second train is	Pick one.
A) 60 kmph B) 66 kmph C) 72 kmph D) 99 kmph E) 89 kmph
Given that two trains are of same length i.e..150 mtrs   first train passes the km stone in 15 seconds. here we have time and distance so speed=150/15= 
<gadget id="calculator">150/15</gadget>
<output>10</output>
10 m/s   we need to find out the second train speed.   suppose the speed of the 2nd train is x m/s   Relative speed of two trains is (10+x)==&gt; (150+150)/(10+x)=8   ==&gt; (300)/(10+x)=8   ==&gt; 300=80+8x   ==&gt; 300-80=8x   ==&gt; 220=8x   :- x=55/2 m/s   convert m/s into km/ph     (55/2)*(18/5)= 
<gadget id="calculator">  (55/2)*(18/5)</gadget>
<output>99</output>
99kmph   ANSWER:99 kmph
<result>D</result>
A train 150 m long passes a km stone in 15 seconds and another train of the same length travelling in opposite direction in 8 seconds.The speed of the second train is