640 centimeters in kilometers

Result

The conversion result is: 640 centimeters is equivalent to 0.0064 kilometers.^[1]

Conversion formula
How to convert 640 centimeters to kilometers?

We know (by definition) that: 1 cm = 1e-05 km.

We can set up a proportion to solve for the number of kilometers.

1 cm / 640 cm = 1e-05 km / x km

Now, we cross multiply to solve for our unknown x:

x km = (640 cm / 1 cm) * 1e-05 km → x km = 0.0064 km

Conclusion:

640 cm = 0.0064 km

Conversion in the opposite direction

The inverse of the conversion factor is that 1 kilometer is equal to 156.25 times 640 centimeters.

It can also be expressed as: 640 centimeters is equal to 1 / 156.25 kilometers.

Approximation

An approximate numerical result would be: six hundred and forty centimeters is about zero point zero one kilometers, or alternatively, a kilometer is about zero times six hundred and forty centimeters.