Convert 25 m/s to km/h.

Answer

To convert 25 meters per second (m/s) to kilometers per hour (km/h), we can follow these steps:

### Step 1: Understand the conversion factors
We know that:
- 1 kilometer = 1000 meters
- 1 hour = 3600 seconds

### Step 2: Set up the conversion
We need to convert meters to kilometers and seconds to hours. We can express this as:
\[ \text{Speed in km/h} = \text{Speed in m/s} \times \left(\frac{1 \text{ km}}{1000 \text{ m}}\right) \times \left(\frac{3600 \text{ s}}{1 \text{ h}}\right) \]

### Step 3: Substitute the values
Now, substituting the value of speed:
\[ \text{Speed in km/h} = 25 \text{ m/s} \times \left(\frac{1 \text{ km}}{1000 \text{ m}}\right) \times \left(\frac{3600 \text{ s}}{1 \text{ h}}\right) \]

### Step 4: Simplify the expression
This simplifies to:
\[ \text{Speed in km/h} = 25 \times \frac{3600}{1000} \]

### Step 5: Calculate the multiplication
Now, calculate:
\[ \frac{3600}{1000} = 3.6 \]
So,
\[ \text{Speed in km/h} = 25 \times 3.6 = 90 \]

### Final Answer
Thus, 25 m/s is equal to 90 km/h.

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