Rinku and Swami were going in summer vacation to a hill station decided to travel in a train the train was running late by its expected time the train covers a distance of 300 km at a uniform speed if the speed of the train is increased by 5 kilometre per hour it takes 2 hours less in the journey find the original speed of train
Answers
Distance-Speed-time Problems
The original speed of the train is 25 km/h
Step-by-step explanation:
Let the original speed of the train = x km/h
The distance covered by the train in a specific time = 300 km
Time taken for the train = Distance /speed
= 300/x ………………………… (1)
When the speed of the train was increased by 5 km, the speed is = x+5 km
The time taken to cover the distance at the new speed
= 300 / (x + 5)………...………..(2)
The time decreased by 2 h
Hence;
300/x-300/(x+5)=2
(300 (x+5)-300x)/(x (x+5))=2
(300x+1500- 300x)/((x^2+5x) ) = 2
1500 = 2 (x^2+5x)
Thus;
2 x^2 + 10 x -1500 = 0
x^2 + 5 x -750 = 0
x^2 + 30 x - 25 x - 750 = 0
x (x+30)-25 (x+30) = 0
(x+30)(x-25) =0
Thus;
(x+30) = 0 or (x-25) = 0
Thus;
x = -30 or x = 25
Since the value of speed cannot be negative, the value is 25
Thus, the original speed of the train was 25 km/h
Answer: 25 km/h .plz refer and choose it as brainliest cause I have found the actual time also
Step-by-step explanation:
