If a train runs at 40 kilometre per hour It reaches its destination late by 11 minutes but if it's run at 50 km per hour it is late by 5 minutes only find the distance to be covered by the train .
Answers
Answer:
Let the correct time for the train to complete the journey is x minuets
Then train cover distance in x+11 minuets at speed 40 km\hr =
60
40(x+11)
km
Then train cover distance in x+5 minuets at speed 50 km\hr =
60
50(x+5)
km
Both are same then
60
40(x+11)
=
60
50(x+5)
∴40x+440=50x+250
∴−10x=−190
∴x=19 minutes
hope it is correct
we can't find exact distance bcz in your question the speed for exact time is not given
Answer:
Let the usual time(time without getting late)= x
And usual speed (speed without getting late)=y
Actual distance covered = xy
If it run by 40 km/h it is late by 11min
So we have
40×((x+11)/60)=xy
(40x+440)/60 = xy ……..(1)
If it run by 50km/h it is late by 5 minutes
So we have
50×((x+5)/60) = xy
(50x+250)/60=xy……….(2)
subtract (2) from(1)
-10x +190/60 =0
x=190/600
So it will take 19 minutes to complete the journey.
Put value in equation (2)
(950+250)/60 =xy
xy =20
so it will cover 20 km in each case.
………………………Second way…………………..
…………………………………………………………………………..
Let distance covered = x
And time =y
time = distance /speed
So we have
x/40 = y+11/60
x=40y+22/3
x-40y=22/3
multiply by 5
5x-200y =110/3………………..…(1)
Now again time = distance / speed
So we have
x/50= y+5/60
x-50y=25/6
multiply by 4
4x-200y =100/6
4x-200y=50/3…………………….(2)
sub ( 2 ) from (1)
x= (110-50)/3
x=20
so distance is 20 km