PHARMACEUTICAL CALCULATIONS I
Section I. REVIEW OF BASIC MATHEMATICS
a. Basic arithmetic is always involved in some manner in the solving of
pharmaceutical calculations. Perfecting basic mathematical functions will help to attain
the goal of 100 percent accuracy desired in pharmacy. Because of the need for 100
percent accuracy, no partial credit will be given for setting a problem up correctly if the
answer is incorrect. In pharmacy, the correct answer is more important than the
b. Even if the operations performed in this lesson seem overly simple, do them
for practice/review. Most of the mistakes made by students taking this subcourse are
mistakes in basic mathematics.
Some drugs have dosages expressed in fractions of a grain. Some calculations
will involve fractions, and it is important for you to have the ability to perform all
mathematical procedures with fractions, whole numbers, and decimals.
a. A fraction consists of two parts: the number above the line is called the
NUMERATOR and the number below the line is called the DENOMINATOR.
Example: In the fraction "1/2," 1 is the NUMERATOR and 2 is the
Fill in the blanks:
What is the numerator in 3/4? ____________
The numerator in 3/4 is 3.
What is the numerator in 9/2? _____________
The numerator in 9/2 is 9.