990 decimeters in kilometers

Conversion formula
How to convert 990 decimeters to kilometers?

We know (by definition) that: $1\mathrm{dm}=0.0001\mathrm{km}$

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

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

Conclusion: 990 ⁢ dm = 0.099 ⁢ km

Conversion in the opposite direction

The inverse of the conversion factor is that 1 kilometer is equal to 10.1010101010101 times 990 decimeters.

It can also be expressed as: 990 decimeters is equal to $\frac{1}{\mathrm{10.1010101010101}}$ kilometers.

Approximation

An approximate numerical result would be: nine hundred and ninety decimeters is about zero point one zero kilometers, or alternatively, a kilometer is about ten point zero nine times nine hundred and ninety decimeters.