Chapter 6.3, Problem 53E

Concept Extensions

As we have seen earlier, proportions are often used in medicine dosage calculation. The exercise below have to do with liquid drug preparation, where the weight of the drug is contained in a volume of solution. The description of mg and ml below will help. We will metric units further in Chapter 9.

mg means milligrams (A paper clip weight about a gram. A milligram is about the weight of $\frac{1}{1000}$ of a paper clip.)

ml means milliliters (A liter is a about a quart. A milliliter is about the amount of liquid in $\frac{1}{1000}$ of a quart.)

One way to solve the applications below is to set up the proportion $\frac{mg}{ml}=\frac{mg}{ml}$.

A solution strength of $15$ mg of medicine $1$ ml of solution is available.

If a patient needs $12$ mg of medicine, how many ml do you administer?