What do these metric prefixes represent deci?

Here's how it works:

* deci (d) = 10⁻¹ = 0.1

So, for example:

* decimeter (dm) is one-tenth of a meter (1 dm = 0.1 m)

* deciliter (dL) is one-tenth of a liter (1 dL = 0.1 L)

* decigram (dg) is one-tenth of a gram (1 dg = 0.1 g)