How to Solve Nursing Math Conversions

Many people entering the health-care field wonder why they didn't pay more attention in math class. Only the metric system is used in health care, and conversion math equations are needed frequently. Americans are comfortable with pounds, feet and inches rather than the metric system. In fact, the United States is one of only three nations that doesn't routinely use the metric system in everyday activities.

Things You'll Need

• Calculator (optional)

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Instructions

• 1

  Convert pounds to kilograms. Divide a patient's weight in pounds by 2.2. The result is the patient's weight in kilograms. If a patient weighs 200 lbs., for example, then the conversion equation is 200 divided by 2.2. The result is 90.9kg, which can be rounded to 91kg.

• 2

  Convert kilograms to pounds. Multiply a patient's weight in kilograms by 2.2 to find her weight in pounds. The equation is kilograms x 2.2 = pounds. A patient who weighs 90.9kg, for example, weighs 199.98 lbs., which can be rounded to 200 lbs.

• 3

  Convert a temperature from Fahrenheit to Celsius. Begin by subtracting 32 from the Fahrenheit temperature. Divide the result by 9. Multiply that result by 5, and you have the temperature in Celsius. For example, if a patient's temperature is 98.6 F and you subtract 32, the result is 66.6; 66.6 divided by 9 is 7.4; and 7.4 multiplied by 5 is 37 C.

• 4

  Convert a temperature from Celsius to Fahrenheit. Divide the Celsius number by 5. Multiply the result by 9. Then add that result to 32, which gives you the temperature in Fahrenheit. For example, if a patient's temperature is 37 C, then divide 37 by 5; the result is 7.4. Multiply 7.4 by 9, which results in 66.6. Add 66.6 and 32, and the result is 98.6 F.

• 5

  Multiply inches by 2.54 to convert inches to centimeters. For example, 17 inches multiplied by 2.54 equals 43.18cm, which can be rounded to 43.2cm.

• 6

  Multiply centimeters by 0.39 to convert centimeters to inches. For example, 43.2cm multiplied by 0.39 equals 16.848 inches, which can be rounded to 17 inches.

• 7

  Multiply milliliters by 0.03 to convert milliliters to ounces. For example, multiply 120ml by 0.03, and the result is 3.6 oz.

• 8

  Multiply teaspoons by 4.9 to convert teaspoons to milliliters. For example, multiplying 2 tsp. by 4.9 results in 9.8ml.