Medical Math

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Medical Math

• for Healthcare Professionals

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Medical Math

• All health care workers are required to perform
  simple math calculations when doing various
  tasks.
• Knowing basic math calculations are essential for
  all health care professionals to be successful.

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Numbers

• Numbers are expressed in different forms
• Whole numbers are the counting numbers and zero
  they do not contain decimals or fractions
• Nonwhole numbers are numbers that have decimals
  ex 12.25
• Mixed numbers are whole numbers and a fraction
  ex 12 ½
• Percetages the whole or all of something ex
  12

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Numbers

• Numbers that have more than one digit are defined
  by their place value. For ex
• The number 7777
• Place value
• 7 (thousands)
• 7 (hundreds)
• 7 (tens)
• 7 (ones)
• This number is described by saying seven
  thousand, seven hundred seventy-seven
• Numbers are written with a comma placed to the
  left of every third digit. 7,777

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Numbers

• Numbers indicating less than a whole number are
  placed to the right of a decimal.
• The number 7,777.255 is given the following place
  values
• Place value
• 7, (thousands)
• 7 (hundreds)
• 7 (tens)
• 7. (ones)
• 2 (tenths)
• 5 (hundredths)
• 5 (thousandths)
• It is written 7,777.255 and described as seven
  thousand, seven hundred seventy-seven and two
  hundred and fifty-five thousandths

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Numbers

• Additions- the totaling of two or more numbers
• Subtraction- the opposite of addition taking a
  number away from another number
• Multiplication- a quick easy way to add finding
  the product of two numbers
• Division- the opposite of multiplication the
  process of separating into parts

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The Metric System

• The health care worker is expected to measure and
  calculate weights, heights, and volume in metric
  units of measure.
• Understanding how to convert standard and metric
  units of measure is helpful in various
• settings

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Metric System

• The health care industry uses the metric system
  for measuring. It is used by 90 of the world
  and is known as the International System of
  Units.

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4 Basic Rules of Metric System

1. Numbers indicating less than one unit are always
   written in a decimal form, not as fractions. Ex
   1/100.1 or 1/1000.01 or 1/10000.001
2. When writing decimals, if there is no number
   before the decimal, always write a 0. Ex .1 is
   0.1 or .5 is 0.5
3. Abbreviations for metric terms are never plural
   they are always written in singular form. Ex
   grams is g, not gs liters is L, not Ls. Always
   capitalize the abbreviation for L for liter to
   reduce confusing the lowercase l with the 1.
4. Leave a space between the number and the
   abbreviation, as shown in the following ex 8 g
   or 0.1 dm.

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Metric Terms and Abbreviations
Term Abbreviations Measures In Place of
Meter m length Inch, foot, yard, mile
gram g weight Ounce, pound
liter L volume Fluid ounce, cup, pint, quart, gallon
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Metric Terms and Abbreviations
Term Abbreviations What is Measures
kilo k 1,000 units
hecto h 100 units
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Metric Terms and Abbreviations
Term Abbreviation What is Measures
deci d 1/10 or 0.1 unit
centi c 1/100 or 0.01 unit
milli m 1/1000 or 0.001 unit
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Using the Metric System to Measure

• A meter stick can be used to measure length in
  the following units
• Centimeter (cm)
• Millimeter (mm)
• Meters (m)
• 1 meter is slightly more
• than 3 ft

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Measurements

• Measures of Length
• 1 hectogram 100 meters
• 1.5 hectogram 150 meters
• 1 kilometer 1,000 meters
• 1.5 kilometer 1,500 meteres
• Measures of Weight
• 1 hectogram 100 g
• 1.5 hectogram 150 g
• 1 kilogram 1,000 g
• 1.5 kilogram 1,500 g

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Using Metric System to Measure

• Liters, Milliliters and Cubic Centimeters
• A liter (L) is slightly larger than a quart
• A milliliter (mL) is 1/1000 of a liter
• Cubic Centimeter (CC) are interchangeable with mL
• Scales can be used to measure weight in grams,
  hectograms, and kilograms
• Celsius (C) and Centigrade- the metric measure of
  heat is Celsius or centigrade, which are the
  same.

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Changing Ounces to Millimeters and Cubic
Centimeters (cc)
1 oz medicine 1 oz x 30 cc/mL 30 cc30 mL
8 oz water 8 oz x 30 cc/mL 240 cc 240mL
6 oz soup 6 oz x 30 cc/mL 180 cc 180mL
4 oz juice 4 oz x 30 cc/mL 120 cc 120mL
12 oz soda 12 oz x 30 cc/mL 360 cc 360mL
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Measuring Devices

• Health care workers use various types of
  measuring devices to measure liquid.

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Changing Pounds to Kilograms and Kilograms to
Pounds

• 110 lb changed to kilograms 110 lb x 0.45 kg/lb
  49.5 kg
• 200 lb changed to kg 200 lb x 0.45 x kg/lb 91
  kg
• 50 kg changed to lb 50 kg x 2.2 lb/kg 110 lb
• 91 kg changed to lb 91 kg x 2.2 lb/kg 200 lb
• To change lb to kg, multiply the number of lbs by
  0.45 lb/kg
• To change kg to lb, multiply the number of kg by
  2.2 lb/kg

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Changing Ounces to Grams

• One ounce (oz) 30 grams (g).
• To change ounces to grams, multiply 30 g/oz by
  the number of ounces.
• To change grams to ounces, divide 30 g/oz into
  the number of grams
• 1 oz changed to grams 1 oz x 30 g/oz 30 g
• 8 oz changed to grams 8 oz x 30 g/oz 240 g

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24 hour/Military Time Clock

• Medical facilities frequently use the 24-hour
  clock system. The 24-hour clock system clearly
  states time and eliminates confusion on
  documentation.
• Military time is always expressed in four digits
  and no colons are used to separate hours and
  minutes.
• Always use a 0 to complete the four digit number
  ex for 100am 0100
• Remember to state the time in hundreds
• ex 100 am 0100 zero one hundred hours
  1100 eleven hundred hours (11am)
• Greenwich time- standard time a 12-hour clock

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Military- 24-hour clock