Two men are standing on opposite ends of a 1500 metre long bridge. If they walk towards each other with speeds of 25 m/s and 5 m/s respectively, then how much time (in seconds) will they take to meet each other?

Options

A. 40
B. 50
C. 60
D. 80

Answer

To solve the problem of how long it will take for the two men to meet while walking towards each other on a 1500-meter long bridge, we can follow these steps:

### Step 1: Understand the Problem
We have two men walking towards each other from opposite ends of a bridge that is 1500 meters long. One man walks at a speed of 25 m/s and the other at 5 m/s.

### Step 2: Determine Their Combined Speed
To find out how quickly they are closing the distance between them, we need to add their speeds together.

- Speed of Man 1 = 25 m/s
- Speed of Man 2 = 5 m/s

**Combined Speed = Speed of Man 1 + Speed of Man 2**
\[ \text{Combined Speed} = 25 \, \text{m/s} + 5 \, \text{m/s} = 30 \, \text{m/s} \]

### Step 3: Use the Formula for Time
We can use the formula for time, which is:
\[ \text{Time} = \frac{\text{Distance}}{\text{Speed}} \]
Here, the distance is the length of the bridge (1500 meters) and the speed is their combined speed (30 m/s).

### Step 4: Calculate the Time
Substituting the values into the formula:
\[ \text{Time} = \frac{1500 \, \text{meters}}{30 \, \text{m/s}} \]
\[ \text{Time} = 50 \, \text{seconds} \]

### Conclusion
The two men will take **50 seconds** to meet each other.

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