3 years from now will be 360. We would like I THU
(iv) A train travels a distance of 480 km at a uniform speed. If the speed
Question
3 years from now will be 360. We would like I THU
(iv) A train travels a distance of 480 km at a uniform speed. If the speed had been
8 km/h less, then it would have taken 3 hours more to cover the same distance. We
need to find the speed of the train. a quadratic equation for this???
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Mathematics
1 year
2021-07-15T15:22:51+00:00
2021-07-15T15:22:51+00:00 2 Answers
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Answers ( )
Answer
Let the speed of the train be x km/hr. Then
Time taken to travel a distance of 480km=
x
480
hr
Time taken by the train to travel a distance of 480km with the speed (x−8)km/hr=
x−8
480
hr
It is given that if the speed had been 8km/hr less, then the train would have taken 3 hours more to cover the same distance
∴
x−8
480
=
x
480
+3
⇒
x−8
480
−
x
480
=3⇒
x(x−8)
480(x−x+8)
=3⇒
x(x−8)
480×8
=3
⇒3x(x−8)=480×8⇒x(x−8)=160×8⇒x
2
−8x−1280=0
This is the required quadratic equation.
: ANSWER
The speed of train is = 40 km /hr
: GIVEN
Distance covered = 480 km
if the speed has been 8 km / hr less
: FIND
Speed of the train
: SOLUTION