Questions : A train at 1/3 of its original speed reaches its destination by 4 hours late.Find the original timing.
Answer:
When the train runs at 1/3 of its original speed, the time taken becomes 3T (since time and speed are inversely proportional).
According to the problem, the train is 4 hours late, meaning:
Solving for T:
Thus, the original timing (time taken without delay) is 2 hours.
Alternative :
Here's how to solve this problem:
Understanding the Relationship
- Speed and Time: When speed decreases, time increases, and vice versa. They are inversely proportional.
- The Key: The distance remains the same whether the train travels at its original speed or the reduced speed.
Let's use variables:
- Let 's' be the original speed of the train.
- Let 't' be the original time taken to reach the destination.
- Let 'd' be the distance to the destination.
Formulating Equations
- Original Journey: d = s * t
- Delayed Journey: The train travels at (1/3)s speed and takes t + 4 hours. So, d = (1/3)s * (t + 4)
Solving for 't'
Since the distance is the same in both cases, we can equate the two equations:
s * t = (1/3)s * (t + 4)
We can cancel 's' from both sides:
t = (1/3)(t + 4)
Now, solve for 't':
3t = t + 4
2t = 4
t = 2
Answer:
The original timing of the journey was 2 hours.
