A man riding his bicycle covers 150 metres in 25 seconds. What is his speed in km/hr?

Options

A. 25
B. 21.6
C. 23
D. 20

Answer

To find the speed of a man riding his bicycle in km/hr, 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 = 25 seconds

### Step 3: Calculate the speed in meters per second
Using the formula:
\[ \text{Speed} = \frac{150 \text{ meters}}{25 \text{ seconds}} = 6 \text{ m/s} \]

### Step 4: Convert the speed from m/s to km/hr
To convert meters per second to kilometers per hour, we use the conversion factor:
\[ 1 \text{ m/s} = 3.6 \text{ km/hr} \]
Thus, we multiply the speed in m/s by 3.6:
\[ \text{Speed in km/hr} = 6 \text{ m/s} \times 3.6 = 21.6 \text{ km/hr} \]

### Final Answer
The speed of the man riding his bicycle is:
\[ \text{Speed} = 21.6 \text{ km/hr} \]

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