To convert centimeters to kilometers, we need to know the conversion factors:
1 kilometer = 1,000 meters
1 meter = 100 centimeters
Putting it together, we can express 1 kilometer in terms of centimeters:
1 kilometer = 1,000 meters × 100 centimeters/meter = 100,000 centimeters
Now, to convert 3 centimeters to kilometers, we use the following conversion factor:
\[ \text{Kilometers} = \text{Centimeters} \times \left(\frac{1 \text{ kilometer}}{100,000 \text{ centimeters}}\right) \]
Calculating this gives:
\[ 3 \text{ cm} \times \left(\frac{1 \text{ km}}{100,000 \text{ cm}}\right) = \frac{3}{100,000} \text{ km} = 0.00003 \text{ km} \]
Thus, the answer is: 0.00003 kilometers.