312 decimeters in kilometers
Result
The conversion result is: 312 decimeters is equivalent to 0.0312 kilometers.[1]
Conversion formula
How to convert 312 decimeters to kilometers?
We know (by definition) that: 1 dm = 0.0001 km.
We can set up a proportion to solve for the number of kilometers.
1 dm / 312 dm = 0.0001 km / x km
Now, we cross multiply to solve for our unknown x:
x km = (312 dm / 1 dm) * 0.0001 km → x km = 0.031200000000000002 km
Conclusion:
312 dm = 0.031200000000000002 km

Conversion in the opposite direction
The inverse of the conversion factor is that 1 kilometer is equal to 32.0512820512821 times 312 decimeters.
It can also be expressed as: 312 decimeters is equal to 1 / 32.0512820512821 kilometers.
Approximation
An approximate numerical result would be: three hundred and twelve decimeters is about zero point zero three kilometers, or alternatively, a kilometer is about thirty-two point zero four times three hundred and twelve decimeters.
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.