Joseph can swim 150 m in 60 seconds. What is his speed in km/hour?

Options

A. 9
B. 90
C. 900
D. 9000

Answer

To find Joseph's speed in kilometers per hour, we can follow these steps:

### Step 1: Understand the formula for speed
The formula for speed is given by:
\[ \text{Speed} = \frac{\text{Distance}}{\text{Time}} \]

### Step 2: Identify the distance and time
From the problem, we know:
- Distance = 150 meters
- Time = 60 seconds

### Step 3: Convert the distance from meters to kilometers
Since we need the speed in kilometers per hour, we first convert the distance from meters to kilometers.
1 kilometer = 1000 meters, so:
\[ 150 \text{ meters} = \frac{150}{1000} \text{ kilometers} = 0.15 \text{ kilometers} \]

### Step 4: Convert the time from seconds to hours
Next, we convert the time from seconds to hours.
1 hour = 3600 seconds, so:
\[ 60 \text{ seconds} = \frac{60}{3600} \text{ hours} = \frac{1}{60} \text{ hours} \]

### Step 5: Calculate the speed in kilometers per hour
Now we can plug the converted values into the speed formula:
\[ \text{Speed} = \frac{0.15 \text{ kilometers}}{\frac{1}{60} \text{ hours}} \]

This can be simplified as:
\[ \text{Speed} = 0.15 \times 60 = 9 \text{ kilometers per hour} \]

### Final Answer
Thus, Joseph's speed is:
\[ \text{Speed} = 9 \text{ km/h} \]

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