a train takes 2 hours less for a journey of 300 km of its speed is increased by 5 km per hour from its usual speed find the usual speed of the train
Answers
Answered by
5
This side,.
Here is your Answer ⬇️⬇️
_______________
Let, the usual speed of the train be x km/h
Now, time = distance / speed
So, the train will take time
= 300/x hours
_ _ _ _ _ _ _ _ _ _ _
Speed of the train is increased by 5 km/h
So, speed of the train will be = (x+5)
So, the train will take time
= 300/(x+5) hours
_ _ _ _ _ _ _ _ _ _ _
Now, as per the question, the train will take 2 hours less time,
So, by condition,
300/x - 300/(x+5) = 2
Or, [300(x+5) - 300(x)] / x(x+5) = 2
Or, 300x + 1500 - 300x = 2 * x(x+5)
Or, 1500/2 = x^2 + 5x
Or, x^2 + 5x = 750
Or, x^2 + 5x - 750 = 0
Or, x^2 + 30x - 25x - 750 = 0
Or, x(x+30) - 25(x+30) = 0
Or, (x-25)(x+30) = 0
Or, x = 25,(-30)
Since, speed can't be negative
So, (-30) is not acceptable.
Thus, usual speed of the train = 25 km/h
_ _ _ _ _ _ _ _ _
➡️ Hence, the usual speed of the train is 25 km/h
_______________
Hope this helps,.
If helps, please mark it as brainliest ^_^
_______________
You may follow me, if you wish
_______________
REGARDS, ARNAB✌️
THANK YOU
Here is your Answer ⬇️⬇️
_______________
Let, the usual speed of the train be x km/h
Now, time = distance / speed
So, the train will take time
= 300/x hours
_ _ _ _ _ _ _ _ _ _ _
Speed of the train is increased by 5 km/h
So, speed of the train will be = (x+5)
So, the train will take time
= 300/(x+5) hours
_ _ _ _ _ _ _ _ _ _ _
Now, as per the question, the train will take 2 hours less time,
So, by condition,
300/x - 300/(x+5) = 2
Or, [300(x+5) - 300(x)] / x(x+5) = 2
Or, 300x + 1500 - 300x = 2 * x(x+5)
Or, 1500/2 = x^2 + 5x
Or, x^2 + 5x = 750
Or, x^2 + 5x - 750 = 0
Or, x^2 + 30x - 25x - 750 = 0
Or, x(x+30) - 25(x+30) = 0
Or, (x-25)(x+30) = 0
Or, x = 25,(-30)
Since, speed can't be negative
So, (-30) is not acceptable.
Thus, usual speed of the train = 25 km/h
_ _ _ _ _ _ _ _ _
➡️ Hence, the usual speed of the train is 25 km/h
_______________
Hope this helps,.
If helps, please mark it as brainliest ^_^
_______________
You may follow me, if you wish
_______________
REGARDS, ARNAB✌️
THANK YOU
Vedansh28:
thnk u very very much....
Answered by
0
Answer:
Let the usual speed of the train be y km / hr .
A.T.Q.
300 ( y + 5 ) - 300 y = 2 y ( y + 5 )
y² + 5 y - 750 = 0
y² + 30 y - 25 y - 750 = 0
( y + 30 ( y -25 ) = 0
y = - 30 or y = 25
Since , speed of train can't be negative .
Therefore , the usual speed of the train is 25 km / hr .
Similar questions
Social Sciences,
7 months ago
Computer Science,
7 months ago
Sociology,
1 year ago
Science,
1 year ago
Math,
1 year ago
Biology,
1 year ago