A train 420 m long is running at a speed of 48 km/hr. In what time will it pass a bridge 60 m long? Choose one: A) 40 sec B) 36sec C) 60 sec D) 48 sec E) 18 sec
total length= 420+60= 
<gadget id="calculator">420+60</gadget>
<output>480</output>
480   speed=48km/h=(48*5)/18= 40/3 m/s   time=(480*3)/40= 
<gadget id="calculator">(480*3)/40</gadget>
<output>36</output>
36 sec.   ANSWER:36sec
<result>B</result>
A train 420 m long is running at a speed of 48 km/hr. In what time will it pass a bridge 60 m long?