If a train runs at 40 kmph, it reaches its destination late by 11 min but it if runs at 50 kmph it is late by 5 min. only the correct time for the train to cover its journey is

• 19 min.
  
  If the distance=x km., Time taken@40 kmph =x/40 and @50 kmph=x/50
  Difference between these two time is (11-5)=6 min.=1/10 hour
  So [(x/40)]-[(x/50)]= 1/6, x=20
  Time taken @ 40 kmph=x/40= 20/40= 1/2 hours=30 min.,which is 11 min late
  So correct time=30-11= 19 min.
• 10 years agoHelpfull: Yes(9) No(1)
• let correct time to cover the journey be x..
  and the total distance be y..
  now, when speed=40 kmph ...
  then 40=(y/x+11) so 40x+440=y ==> 40x-y=-440..(i)
  when speed=50kmph
  then 50=(y/x+5) so 50x+250=y ==> 50x-y=-250..(ii)
  now by solving equation we get x=19...and y=1200..
  so the correct time to cover distance is 19hr and distance is 1200 km...
• 10 years agoHelpfull: Yes(1) No(6)
• 20 km distance in 19 m is correct time for journey.
• 10 years agoHelpfull: Yes(1) No(1)
• pl. read [(x/40)]-[( x/50)]= 1/10 in my earlier solution instead of
  [(x/40)]-[(x/50)]= 1/6
  On solving distance,x=20 km & correct time=19 min
• 10 years agoHelpfull: Yes(1) No(2)
• right time is 19 and the speed required to reach by that time is 63kmph
• 10 years agoHelpfull: Yes(0) No(0)