Question

The density of a stone is 1406 mg/ml and its mass is 9842 mg what is its volume?

Answer 1

You can find the volume by using the formula of density
$d=\frac{m}{v}$

where d is the density, m is the mass and v is the volume

You have to solve the formula for v like this:
$v = \frac{m}{d}$

you have the density and the mass so you just have to replace the variables in the formula with the values they are giving you, like this:

$v = \frac{9842mg}{1406 \frac{mg}{ml} } = 7ml$

The volume of the stone is 7ml