Please help me convert metric units

I’m hopeless with arithmetic. I need to convert pg/ml to ng/dl. That’s picograms per mililiter to nanograms per deciliter. I know it’s all powers of 10, but I’m still a little lost.

I think I multiply picograms by 1000 to get nanograms and multiply ml by 100 to get dl so I think that means if I multiply the pg/ml by 10, I get ng/dl. Is that right?

There are numerous online metric converters. Here’s onesuch: http://www.onlineconversion.com/

Google “metric conversion” if that doesn’t have what you need. Lots of pages out there that do this.

Or in short, yes multiply by 10, your arithmetic is fine.

oh, you actually divide ml by 100 to get dl but the end result is 10 is the correct conversion

1 pg = 0.001 ng.
1 mL = 0.1 dL.

Therefore, 1 pg/mL = 0.001 ng/0.1 dL = 0.01 ng/dL.

You have to carry the units through along with the numbers. For each component unit you are starting with, you can substitute the equivalent number of the unit you want to end up with. Then you can multiply all the numbers, and that gives you a conversion factor.

1000 pg = 1 ng, which means: (1 ng / 1000 pg) = 1
1 dl = 100 ml, which means: (100 ml / 1 dl) = 1

Multiplying by 1 doesn’t change the quantity.

So:



   pg          pg    100 ml     1 ng         N     ng
N ----  =  N  ---- x ------  x -------   =  ----  ----
   ml          ml     1 dl     1000 pg       10    dl


Which means 1 pg/ml = 0.1 ng/dl.

The way we were taught to do it in school is pretty similar to how the OP states it, but we were taught to write down all the steps like this - and then cross out all the stuff that “negates” each other.

ng/dl

pg/ml * (1000 ng/pg) / (100 dl/ml) =

(###1000/100) (pgngml)/(mlpg*dl)

If you just want an answer, you can use Google’s calculator. Type in stuff like “4 liters per square meter in gallons per square yard” and you get the answer you’re looking for without the headache. :slight_smile:

ARGH! didn’t mean to submit
…=
(###*10) ng/dl

ta-daaah! Of course it looks better when you can write the numerator on top of the denominator and actually cross stuff off in the second step.

Ah well, at least i wasn’t the only one to submit a wrong answer!

Having checked my arithmetic i agree with scr4, in other words divide pg/ml by 10 to get ng/dl.

Simply put “picograms per milliliter to nanograms per deciliter” into a Google search bar.

Result

errr… What Nanoda said.

Er, of course, the conversion factor may be wrong… decilitre, not centilitre. My methodology was okay, though. The error is findable.

I’ll shut up now. :: blush ::