Convert 72 km/h into m/s.

Answer

To convert 72 km/h into m/s, we can follow these steps:

### Step 1: Understand the conversion factors
1 kilometer (km) is equal to 1000 meters (m), and 1 hour (h) is equal to 3600 seconds (s) since 1 hour = 60 minutes and 1 minute = 60 seconds (60 * 60 = 3600 seconds).

### Step 2: Set up the conversion formula
To convert from kilometers per hour to meters per second, we can use the following formula:
\[ \text{Speed in m/s} = \text{Speed in km/h} \times \frac{1000 \text{ m}}{1 \text{ km}} \times \frac{1 \text{ h}}{3600 \text{ s}} \]

### Step 3: Substitute the given speed into the formula
Substituting 72 km/h into the formula:
\[ \text{Speed in m/s} = 72 \times \frac{1000}{3600} \]

### Step 4: Simplify the expression
Now, we can simplify the fraction:
\[ \frac{1000}{3600} = \frac{1000 \div 100}{3600 \div 100} = \frac{10}{36} = \frac{5}{18} \]
So, we can rewrite the equation as:
\[ \text{Speed in m/s} = 72 \times \frac{5}{18} \]

### Step 5: Calculate the final speed
Now, we can perform the multiplication:
\[ 72 \div 18 = 4 \]
Then, multiply by 5:
\[ 4 \times 5 = 20 \]

### Final Answer
Thus, the speed of 72 km/h is equal to 20 m/s.

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