`128 cm = "_________"km `

Answer

To convert 128 cm to kilometers, we need to follow these steps:

### Step 1: Convert centimeters to meters
We know that:
1 meter (m) = 100 centimeters (cm)

To convert centimeters to meters, we can use the formula:
\[ \text{meters} = \frac{\text{centimeters}}{100} \]

So for 128 cm:
\[ \text{meters} = \frac{128 \text{ cm}}{100} = 1.28 \text{ m} \]

### Step 2: Convert meters to kilometers
Next, we know that:
1 kilometer (km) = 1000 meters (m)

To convert meters to kilometers, we can use the formula:
\[ \text{kilometers} = \frac{\text{meters}}{1000} \]

So for 1.28 m:
\[ \text{kilometers} = \frac{1.28 \text{ m}}{1000} = 0.00128 \text{ km} \]

### Final Answer
Therefore,
\[ 128 \text{ cm} = 0.00128 \text{ km} \]

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