40 decimeters in meters

Conversion formula
How to convert 40 decimeters to meters?

We know (by definition) that: $1\mathrm{dm}=0.1\mathrm{m}$

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

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

Conclusion: 40 ⁢ dm = 4.0 ⁢ m

Conversion in the opposite direction

The inverse of the conversion factor is that 1 meter is equal to 0.25 times 40 decimeters.

It can also be expressed as: 40 decimeters is equal to $\frac{1}{\mathrm{0.25}}$ meters.

Approximation

An approximate numerical result would be: forty decimeters is about zero meters, or alternatively, a meter is about zero times forty decimeters.