A train covered a certain distance at a uniform speed. If the train would have been 10 km/h faster, it would have taken 2 hours less than the scheduled time. And, if the train were slower by 10 km/h, it would have taken 3 hours more than the scheduled time. Find the distance covered by the train.
Speed is equal to the distance traveled divided by time.
Answer: The distance covered by the train will be 600 km.
Let's find the distance covered by the train.
Explanation:
Let's consider the time taken to be 't'
Let the speed be 'x' and distance be 'd'
Distance = Speed × Time
By substituting in the above equation we get,
d = xt ----------------- (1)
Case 1: When speed is increased by 10 km/h and time is decreased by 2 hours.
New speed = x + 10, New time = t - 2
Substituting the values we get,
d = (x + 10)(t – 2)
d = xt – 2x + 10t - 20
d = d – 2x + 10t - 20 [since, d = xt from equation (1)]
10t – 2x = 20 ---------------------- (2)
Case 2: When speed is reduced by 10 km/h, time increases by 3 hours.
New speed = x - 10, New time = t + 3
Substituting the values we get,
d = (x – 10)(t + 3)
d = xt + 3x -10t – 30
d = d + 3x -10t – 30 [since, d = xt from equation (1)]
3x -10t = 30 ------------------------- (3)
Adding equation (2) and (3)
10t - 2x + 3x -10t = 20 + 30
x = 50
To calculate the value of time, substitute the value of x in equation (2)
10t – (2 × 50) = 20
10t = 20 + 100
10t = 120
t = 12 hours
Now, to calculate the distance, substitute the value of t and x in equation (1)
d = xt
d = 50 × 12
d = 600 km
Thus, the distance covered by the train is 600 km.
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