640 centimeters in kilometers

Conversion

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.

\frac{1 cm}{640 cm} = \frac{1e-05 km}{x km}

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

x km = \frac{640 cm}{1 cm} * 1e-05 km \to x km = 0.0064 km

Conclusion: $640 cm = 0.0064 km$

640 centimeters is equivalent to 0.0064 kilometers

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 $\frac{1}{156.25}$ 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.

Units involved

This is how the units in this conversion are defined:

Centimeters

A centimetre (symbol cm) or centimeter (American spelling) is a unit of length in the metric system, equal to one hundredth of a metre, centi being the SI prefix for a factor of 1⁄100.

Wikipedia page of centimeters

Kilometers

The kilometre or kilometer (American spelling) is a unit of length in the metric system, equal to one thousand metres (kilo being the SI prefix for 1000). It is now the measurement unit used officially for expressing distances between geographical places on land in most of the world; notable exceptions are the United States and the road network of the United Kingdom where the statute mile is the official unit used.

Wikipedia page of kilometers

Footnotes

[1] The precision is 15 significant digits (fourteen digits to the right of the decimal point).

Results may contain small errors due to the use of floating point arithmetic.

Conversion

Conversion formula How to convert 640 centimeters to kilometers?

Conversion in the opposite direction

Approximation

Conversion formula
How to convert 640 centimeters to kilometers?