25 kilometers in millimeters

Conversion formula
How to convert 25 kilometers to millimeters?

We know (by definition) that: $1\mathrm{km}=1000000\mathrm{mm}$

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

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

Conclusion: 25 ⁢ km = 25000000 ⁢ mm

Conversion in the opposite direction

The inverse of the conversion factor is that 1 millimeter is equal to 4e-08 times 25 kilometers.

It can also be expressed as: 25 kilometers is equal to $\frac{1}{\mathrm{4e-08}}$ millimeters.

Approximation

An approximate numerical result would be: twenty-five kilometers is about twenty-five million millimeters, or alternatively, a millimeter is about zero times twenty-five kilometers.