How to convert 100 millimeters to decimeters?
We know (by definition) that:
We can set up a proportion to solve for the number of decimeters.
Now, we cross multiply to solve for our unknown :
Conversion in the opposite direction
The inverse of the conversion factor is that 1 decimeter is equal to 1 times 100 millimeters.
It can also be expressed as: 100 millimeters is equal to decimeters.
An approximate numerical result would be: one hundred millimeters is about zero decimeters, or alternatively, a decimeter is about zero times one hundred millimeters.
 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.