A train travels 360km with uniform speed. the speed of train is increased by 5km/hr, it takes 48 minutes less to cover the same distance. find the initial speed of the train.
Answers
Answer:
mark brainliest
Step-by-step explanation:
Correct answer is
45
Let x= Original Speed
we know that
speed
distance
=time
So as per the question the following equation can be formed
x
360
−
x+5
360
=
60
48
[1 hour = 60 minutes]
⇒
x
1
−
x+5
1
=
60
48
⋅
360
1
⇒
x
2
+5x
5
=
450
1
⇒x
2
+5x−2250=0
⇒x
2
−45x+50x−2250=0
⇒x(x−45)+50(x−45)=0
⇒(x−45)(x+50)=0
x=45,−50
As the speed can't be negative so,
x=45
Answer:let the speed of train be xkm/h
s=360 km,speed =distance/time
x=360/time1, time1=360/x ,on increasing speed 5km/h,final speed will be (x+5)
it will take 48 minute less time to cover same distance,since 60 min =1 h
48 min=48/60 h,
time2=time1-48/60
time2 =360/x-48/60
speed2 =distance/time 2, x+5=360/360/x-4/5
x+5=360/360*5-4x/5x
x+5=360*5x/1800-4x , (x+5) (1800-4x)=1800x
x=450 km/h