PHARMACEUTICAL MATH I PHRA 1209

Most prescriptions are written using the metric system therefore, most calculations involve using the metric system. The metric system uses decimals.

Multiplication of Decimals:

• multiply the numbers together

• count the number of places to right of the decimals in both the numbers multiplied

• starting at the right, move the decimal place one place to the left for decimal place counted

Division of Decimals:

the following terms are used in division:

• the first step is to remove the decimal point from the divisor by moving the decimal point to the far right and count the number of times moved.

• the second step is to move the decimals in the dividend to the right the same number of times the decimal was moved in the divisor.

• divide the dividend by the divisor and reposition the decimal into the proper place in the quotient

Addition of Decimals:

• take all the numbers and line up the decimal points

• add the numbers and leave the decimal point in the answer in the same position as the other decimal points

Subtraction of Decimals:

• take the numbers and line up the decimal points

• subtract the numbers and leave the decimal point in the answer in the same position as the other decimal points