If the speed of a boat in still water is u km/h and the speed of the stream is v km/h , then the speed of the boat upstream is ____km/h

Answer

To find the speed of the boat upstream when the speed of the boat in still water is \( u \) km/h and the speed of the stream is \( v \) km/h, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Direction of Movement**:
- When the boat is moving upstream, it is going against the current of the stream.

2. **Identify the Speeds**:
- Speed of the boat in still water = \( u \) km/h
- Speed of the stream = \( v \) km/h

3. **Calculate the Effective Speed Upstream**:
- When moving upstream, the speed of the stream reduces the effective speed of the boat. Therefore, we need to subtract the speed of the stream from the speed of the boat in still water.
- The formula for the speed of the boat upstream is:
\[ \text{Speed upstream} = u - v \]

4. **Conclusion**:
- Thus, the speed of the boat upstream is \( (u - v) \) km/h.

### Final Answer:
The speed of the boat upstream is \( (u - v) \) km/h.

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