(x ml)(4.8 g/ml) = 19.2 g (write an equation that represents the problem)
x ml = (19.2 g)/(4.8 g/ml) (solve it: Divide both sides by 4.8 g/ml)
x ml = (19.2/4.8) ml = 4 ml (evaluate the result)
Note that in problems of this sort, it is often quite helpful to carry the units along with the numbers. That way, you have assurance that the units of the answer are what you need them to be. Of course, you need to remember your fractions: Dividing by g/ml is the same as multiplying by ml/g.
x ml = (19.2 g)/(4.8 g/ml) (solve it: Divide both sides by 4.8 g/ml)
x ml = (19.2/4.8) ml = 4 ml (evaluate the result)
Note that in problems of this sort, it is often quite helpful to carry the units along with the numbers. That way, you have assurance that the units of the answer are what you need them to be. Of course, you need to remember your fractions: Dividing by g/ml is the same as multiplying by ml/g.
