A train 300 m long is running at a speed of 78 km/hr. If it crosses a tunnel in 1 min, then the length of the tunnel is? Choose one
A) 298 m	B) 279 m	C) 500 m	D) 289 m	E) 1000 m
Speed = 78 * 5/18 = 65/3 m/sec.   Time = 1 min = 60 sec.   Let the length of the train be x meters.   Then, (300 + x)/60 = 65/3   x = 1000 m.   Answer: 1000 m
<result>E</result>
A train 300 m long is running at a speed of 78 km/hr. If it crosses a tunnel in 1 min, then the length of the tunnel is?