A train travelling at a speed of 75 mph enters a tunnel 7/2 miles long. The train is 1/4 mile long. How long does it take for the train to pass through the tunnel from the moment the front enters to the moment the rear emerges? A.1 min B.3 min C.5 min D.6 min E.None of these

1 Answer

Answer :

Answer – B (3 min)

Explanation – Actually train is covering length of tunnel + its own

length here

so total distance = 7/2 + 1/4= 15/4 miles

time= distance /speed

time= (15/4) / 75 = 1/20 hour

(1/20)x60 = 3 min

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