If the speed of a swimmer in still water is 9 km/h. Find the upstream speed of the swimmer, when the river, is flowing with the speed of 6 km/h?

Options

A. 15 km/h
B. 18 km/h
C. 3 km/h
D. 12 km/h

Answer

To find the upstream speed of the swimmer, we can use the following formula:

**Upstream Speed = Speed of Swimmer in Still Water - Speed of River Current**

### Step-by-Step Solution:

1. **Identify the Speed of the Swimmer in Still Water**:
The speed of the swimmer in still water is given as 9 km/h.

2. **Identify the Speed of the River Current**:
The speed of the river current is given as 6 km/h.

3. **Apply the Formula for Upstream Speed**:
We can substitute the values into the formula:
\[ \text{Upstream Speed} = \text{Speed of Swimmer in Still Water} - \text{Speed of River Current} \]
\[ \text{Upstream Speed} = 9 \text{ km/h} - 6 \text{ km/h} \]

4. **Calculate the Upstream Speed**:
\[ \text{Upstream Speed} = 3 \text{ km/h} \]

Thus, the upstream speed of the swimmer is **3 km/h**.