Density is equal to the mass divided by the volume. Usually density is represented by the Greek letter rho, however here I will just use the letter "r". So then:
r = M/V and therefore
M = rV and therefore
V = M/r
So if you know any two of r, M, or V, you can find the missing piece of information.
A formula.
Formula
Formula
Formula
I suspect you are looking for "formula".
By definition, density = mass / volume.
It is a mapping.It need not be a function. For example, f(x) = sqrt(x) where x is a non-negative real number, is a relationship but, because it is one-to-many, it is not a function.
Mass is the weight of an object/liquid/gas. Volume is the amount of space it occupies (although it does not need to completely "fill up" the container it is in, such as a gas that has particles that are not touching side by side like a solid). Density is the relationship between mass and volume. The formula is D=m/v or Density=Mass (divided by) Volume. It determines how solid something is (for example, a gas would not be considered very dense because it's particles are so far apart).
Formula
Formula
A formula.
To convert between mass and volume you need the density of the substance. Density = mass/volume. It is not clear what you mean by count. If you are thinking of large scale objects then if they are all alike, you can convert mass to count if you know the mass of one of them. I wonder if you are thinking of chemical quantity expressed in moles? The conversion in this case is moles = mass/molar mass.
e formula
Formula
Formula
I suspect you are looking for "formula".
Density is a measure of how much mass is contained in a given volume. It describes how tightly packed the particles of a substance are. Density is important because it affects the physical properties of a material, such as whether it will float or sink in a liquid.