Question

What does a measurement of 3853 pg/mg mean?

Answer 1

A measurement of 3853 pg/mg tells you that there are 3853 pg (picograms) of a substance in 1 mg (milligram) of the sample.

Explanation:

To put it another way, the mass of sample is

`(1 × 10^"-3" color(red)(cancel(color(black)("g"))))/(3853 × 10^"-12" color(red)(cancel(color(black)("g")))) = "259 500 times the mass of the substance"`.

If we had a pile of sand grains all the same size, there would be 1 white grain in 259 500 brown grains, or about 4 white grains in a million brown ones.