A train 800 m long is running at a speed of 78 km/hr. If it crosses a tunnel in 2 min, then the length of the tunnel is? Choose the correct choice from the following options:	A) 2898	B) 1800	C) 500	D) 297	E) 435
Speed = 78 * 5/18 = 65/3 m/sec.   Time = 2 min = 120 sec.   Let the length of the train be x meters.   Then, (800 + x)/120 = 65/3   x = 1800 m.   Answer: 1800
<result>B</result>
A train 800 m long is running at a speed of 78 km/hr. If it crosses a tunnel in 2 min, then the length of the tunnel is?