# How do you get the mass with volume and no density?

##### 1 Answer

Well, you could always just put it onto a scale to find the mass. But assuming you aren't talking about a laboratory setting...

The general formula is:

#\mathbf(rho = m/V)# where

#rho# isdensityin#"g/mL"# ifmass#m# is in#"g"# andvolume#V# is in#"mL"# .

So to get the mass...

#color(blue)(m = rhoV)#

Or to get the volume...

#color(blue)(V = m/rho)#

When you have the volume and *not* the density, and you want to find mass, **you will need to find the density yourself**. It's often readily available on the internet.

Just replace "[...]" with the object you want, and if it's not exactly what you need, consider it an estimate.

*These days, you should be able to search for the density of any common object.*

When you have the density and volume but *not* the mass, then just **make up a mass**.

You shouldn't need specific numbers to do a problem. You can always solve a problem *in general* and get a solution formula. If you need to, just make up some numbers that you know how to use.