A train travelling at a speed of 76 mph enters a tunnel 9/2 miles long. The train is 1/4 mile long.

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10 May 2017 Trains

A train travelling at a speed of 76 mph enters a tunnel 9/2 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?

OPtion

OPTION
1) 3 minutes 75 seconds
2) 3 minutes 40 seconds
3) 3.45 minutes
4) 3.70 minutes
5) 3 minutes 55 seconds
6) 3 minutes 35 seconds
7) 3 minutes 30 seconds
8) 3 minutes 25 seconds
9) 3 minutes 45 seconds
10) None of these

Solution

Total Distance covered = 9/2 + 1/4 = 19/4
Time Taken = Distance/Speed = (19/4)*(1/76) = 3.75 min = 3 min 45 seconds
Option 9)

Correct Option: 9 Best Solution (10)

Devesh Gupta   7 years AGO

Total distance covered by train = length of tunnel + length of train
= (9/2)+(1/4) = 19/4 miles

Speed of train = 76 mph

time = distance/speed

time = 19/(4*76) hrs = (19*60)/(4*76)

time = 3.75 minutes = 3 minutes (0.75*60) seconds

time = 3 minutes 45 seconds

Like? Yes (3) | No   

Mukund Manohar   7 years AGO

Distance = 9/2 + 1/4 = 19/4 miles
Required Time = (19/4)/76 = 19/(4*76) = 1/16 hours
= 3.75 minutes = 3 minutes 45 seconds

Like? Yes (1) | No   

G.S.Kantharao   7 years AGO

Speed of the train=76mph
Speed per minute=76/60mile
Length of the tunnel =9/2 miles
Length of the train =1/4 mile
Total length =19/4mile
Time taken to cross=Distance/Time = (19/4)÷(76/60) =(19*60)/(4*76)=15/4minutes=3minutes 45seconds.
My option is 9

Like? Yes (1) | No   

Haritha Mummidivarapu   7 years AGO

total distance = 1/4 + 9/2
speed of train = 76mph
time = distance / speed = 0.0625 hr = 0.0625 * 60 mins = 3.75 mins = 3 mins 45 sec

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Amarnath Kumar Upadhyay   7 years AGO

t=d/t
so (9/2+1/4)*1.6/76*1.6 //multiply 1.6 to change in kmh
t=3.75 min
t= 3 min 45 sec //0.75 min * 60=45 sec

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ganesh chemanchula   7 years AGO

total distance=9/2+1/4=19/4 miles
speed=76mph
time=distance/speed=(19/4)*(1/76)=1/16 hrs
that means 3 minutes and 45 seconds

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MOHIT KUMAR   7 years AGO

Distance=1/2+9/2=4.75 mile
speed=76 mph
time=d/s=4.75*60*60/76
=225 seconds
=3 min 45 seconds

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jyothi chhabria   7 years AGO

total distance is 9/2 +1/4=19/4 miles
time= d/s=19/4×76=1/16 hrs
60×60/16=225sec= 3min 45 sec

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Priyanka   7 years AGO

speed=76mph=>121.6kmph
1mile=1.6km
distance=9/2mile+1/4mile
=19/4miles=>7.6km
time=distance/speed
=7.6/121.6
=1/16hr
=1*60/16min
=15/4min
=3min45sec

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khushbu shrimal   7 years AGO

total distance=9/2+1/4=19/4 miles
time =19/(4×76) =1/16 =60/16 =3 min (12/16) sec = 3 min 45 sec

Like? Yes | No