31 miles in kilometers

Conversion formula
How to convert 31 miles to kilometers?

We know (by definition) that: $1\mathrm{mile}=1.609344\mathrm{km}$

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

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

Conclusion: 31 ⁢ mile = 49.889664 ⁢ km

Conversion in the opposite direction

The inverse of the conversion factor is that 1 kilometer is equal to 0.0200442320076559 times 31 miles.

It can also be expressed as: 31 miles is equal to $\frac{1}{\mathrm{0.0200442320076559}}$ kilometers.

Approximation

An approximate numerical result would be: thirty-one miles is about forty-nine point eight nine kilometers, or alternatively, a kilometer is about zero point zero two times thirty-one miles.