# Math Help - to convert mg to kg

1. ## to convert mg to kg

Hi

I want help to convert mg to kg

ex: 1250mg --- > kg

Are we multiply 1250mg X 10^-3

or multiply 1250mg X 10^-6

2. $10^{-6}$

You know, I presume, that 1 kg is much larger than 1 g. So 1250 mg will be a much smaller number of kg.

A more detailed way of looking at it: There are 1000 "milli"gram in a gram: $1= \frac{1000 mg}{1 g}$ and 1000 grams in a "kilo"gram.

So $(1000 mg/g)(1000 g/kg)= 1000000 mg/kg= 10^6 mg/kg$- the "grams" cancel.

Since you have "mg" and want to end with kg, you need to multiply by kg/mg: mg(kg/mg)= kg

$10^6 mg/kg$ is the same as $10^{-6} kg/mg$