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A train travels at a particular speed for a duration of one hour, after which one
of its engine malfunctions reducing its speed to 3/5th of the actual speed before the
occurrence of fault in engine. It travels at this speed for 2 hours to reach at its
destination. If the fault had occurred 50 miles later on, the train would have reached
its destination 45 minutes early. Find the distance traveled by the train.
Let the actual speed of train be X miles/hour.
after fault its speed will be reduced to 3X/5 miles/hour.
If we could find the speed of the train, we will get the solution!!!
by seeing one can find that time difference( 45 minutes) occur between two cases,
in the 50 miles distance traveled by the train at two different speeds(X and 3X/5).
=> If the time taken to cover 50 miles at speed 3X/5 is 't' hours then time taken to
travel 50 miles at speed X is t-(45/60) = (t-0.75) hours.
We can write ...=> (3X/5)*t = X*[t-0.75] = 50 miles -->(i)
solving we get... t=15/8 hours.
then substituting value of 't' in first term of eq. (i) => (3X/5)*15/8=50
solving we get... X= 400/9 miles/hour.
Answer : So, solving the problem with first case we get the distance traveled
by the train as 97.77 miles.



  
Total Answers and Comments: 3 Last Update: July 30, 2006     Asked by: Beena 
  
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 Best Rated Answer
Submitted by: Praveen
 
Case first : let us assume speed to train be x miles/hours Total distance travelled in case 1 = x*1 + 3x/5*2 = 11x/5 milesCase 2 : Total distance travelled in case 2 = x+50 + 3x/5*(2-45/60) = 50 +7x/4 comparing these two equations we have x= 1000/9Hence total distance =11x/5 = 11*1000/9 *1/5 = 244.44 miles

Above answer was rated as good by the following members:
starsun
December 06, 2005 05:37:06   #1  
rahul        

RE: A train travels at a particular speed for a durati...

Let speed be s and distancs be d

for the first case

1*s +2*3s/5 d

so d/s + d/(3s/5) + 45/60 50/s +(d-50)/(3s/5)

substitute value of d from eqn above

s 498/8

and will be 100 miles

quite an easy way!


 
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January 12, 2006 09:21:28   #2  
Praveen        

RE: A train travels at a particular speed for a durati...
Case first : let us assume speed to train be x miles/hours Total distance travelled in case 1 x*1 + 3x/5*2 11x/5 milesCase 2 : Total distance travelled in case 2 x+50 + 3x/5*(2-45/60) 50 +7x/4 comparing these two equations we have x 1000/9Hence total distance 11x/5 11*1000/9 *1/5 244.44 miles
 
Is this answer useful? Yes | NoAnswer is useful 1   Answer is not useful 0Overall Rating: +1    
July 30, 2006 19:00:54   #3  
Scott McGillivray        

RE: A train travels at a particular speed for a durati...
I get 366.67 miles.
Let v train full velocity
Let d distance
Case 1 - train goes (1 hour * v) + (2 hours * 3 v / 5) d Therefore d v * 2.2 hours
Case 2 - train covers 50 miles 45 minutes faster at v than at v * 3/5
( 50 miles / (.75 hours) ) v * 2 / 5 0.4 v
v 166 miles / hourplug v into answer from 1 and you get d 166 mph * 2.2 hours 366.67 miles.

 
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