b. Example 2: Express 30 liters in terms of milliliters. (There are 1000 ml in 1
liter.)
IF 1000 ml
THEN
X ml .
1 liter
=
30 liters
1 X = 1000 30 liters
X = 30,000 ml (answer)
Section IV. THE APOTHECARY SYSTEM
1-12. INTRODUCTION
Several systems of weight and measure are used currently in the United States.
This is an unfortunate situation in the medical field, but until the metric system is
universally adopted in this country, you must remain flexible and familiar with some of
the commonly encountered units from other systems of measurement. Ultimately, all
calculations will be performed in the metric system. The metric system is the official
system for use in the U.S. Army. Conversion factors or equivalents are discussed and
presented later in this lesson to enable you to convert quickly and accurately from other
systems to the metric system. GIVEN A CALCULATION INVOLVING UNITS IN
ANOTHER SYSTEM OF MEASURE, CONVERT TO AND WORK WITHIN THE
METRIC SYSTEM.
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APOTHECARY WEIGHT
Several years ago, the apothecary system of measure was widely used in
calculations pertaining to the administration of medications. Recently, the apothecary
system has been used less and less in favor of the metric system. One unit in the
apothecary system (see Table 1-7) is still seen on some drug labels. As you see from
Table 1-7, the abbreviation for grain is gr.
Apothecary
Abbreviation
grain
gr.
Table 1-7. A commonly encountered apothecary weight unit.
MD0913
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