Importance of Medical Math: Overcoming Math Anxiety and Learning Essential Calculations

1. Chapter 5 Medical Math

2. Importance of Math • Frequently used in health care • Requires 100 percent accuracy • Errors can have dire consequences

3. Math Anxiety • Common problem • Impedes performance • Can be overcome • False beliefs versus reality

4. Question • True or False: • If a person currently has problems with math, it can be assumed that it will always be a problem.

5. Answer • False • Math anxiety • Learned behavior • Can be overcome

6. Basic Calculations • Whole numbers • Add • Subtract • Multiply • Divide

7. Decimals • Expressed in units of ten • Placement values • Zero used before decimal point if number begins to right of decimal point

8. Working with Decimals • Placement of decimal • Add • Subtract • Multiply • Divide

9. Fractions • Represents part of a whole • Numerator • Denominator

10. Working with Fractions • Add • Subtract • Multiply • Divide • Improper fractions • Reducing fractions

11. Percentages • Expresses whole or part of a whole • Whole expressed as 100 percent • Convert to decimal • Then perform calculation

12. Ratios • Show relationships between numbers or like values • Compare presence of one value to another • Frequently used to express strength of solution

13. Converting Decimals, Fractions, and Percentages • Decimal to fraction • Decimal to percentage • Fraction to decimal • Fraction to percentage

14. Converting Decimals, Fractions, and Percentages • Percentage to decimal • Percentage to fraction • Percentage to ratio • Ratio to percentage

15. Question • True or False: • ¾, 75%, and 0.75 are all equivalent.

16. Answer • True • ¾ • Fraction • If converted to percentage = 75% • If converted to decimal = 0.75

17. Rounding Numbers • What does it mean? • Round up • Round down

18. Question • What is 2.346 rounded to the nearest tenth? • 2 • 2.3 • 2.35

19. Answer • B. 2.3 • 2.346 rounded to nearest tenth = 2.3 • 2.346 rounded to nearest whole number = 2 • 2.346 rounded to nearest hundredth = 2.35

20. Solving with Proportions • Statement of equality between two ratios • Used for converting from one unit to another • Steps for solving problems

21. Estimating • Anticipate results • Determine if answer is reasonable • Calculate approximate answer

22. Question • If the order is to give 2 grams of a medication and you have 1,000 milligram tablets, how many tablets would you give? • ½ tablet • 2 tablets • 4 tablets

23. Answer • B. 2 tablets • 1 gram = 1,000 milligrams • 2 grams = 2,000 milligrams or 2 tablets • ½ tablet = 500 milligrams • 0.5 grams (too little) • 4 tablets = 4,000 milligrams • 4 grams (too much)

24. Military Time • 24-hour clock • No AM or PM • Avoids errors • 12th hour = noon • 24th hour = midnight

25. Question • True or False: • The military time of 1600 is the same as 6 p.m. traditional time.

26. Answer • False • 1600 = 4 p.m. • 6 p.m. would be 1800 military time

27. Military Clock

28. Roman Numerals • Arabic versus Roman numerals • All numbers from seven key numerals • I, V, X, L, C, D, and M

29. Roman Numerals Rules • If smaller numeral is in front of larger numeral • If smaller numeral is after larger numeral • If same numeral is repeated • Limit to number of times numeral is placed next to itself

30. Question • How would 43 be written in Roman numerals? • XLIII • XXXXIII • XXXI

31. Answer • A. XLIII • XLIII = 43 • XXXXIII incorrect • Same numeral cannot be placed next to itself more than three times • XXXI = 31

32. Angles • Comparison to reference plane • Using angles in health care • Measured in units • Degrees

33. Angles

34. Systems of Measurement • Three systems • Distance • Length • Capacity • Volume • Mass • Weight

35. Systems of Measurement • Nomenclature • Method of naming • Need to convert between systems

36. Household System • Used in U.S. • Nomenclature for distance/length • Nomenclature for capacity/volume • Nomenclature for mass/weight • Common equivalents • How to convert

37. Question • Which of the following is a capacity/volume unit in the household system? • Inch • Pound • Ounce

38. Answer • C. Ounce • Ounce • Unit of measurement for capacity/volume in household system • Also unit of measurement for mass/weight

39. Answer • C. Ounce • Inch • Measurement for distance/length • Pound • Measurement for mass/weight

40. Metric System • Used in Europe • More accurate • Easier to use • Based on unit of ten • Convert units by moving decimal • Common prefixes

41. Metric System • Nomenclature for distance/length • Nomenclature for capacity/volume • Nomenclature for mass/weight

42. Question • How many centimeters are there in one meter? • 10 • 100 • 1000

43. Answer • B. 100 • Meter • Base unit for distance/length in metric system • Centi = 1/100 • 1 meter = 100 centimeters

44. Apothecary System • Oldest and least used • Nomenclature for capacity/volume • Nomenclature for mass/weight • Common equivalents • How to convert • Roman numerals and abbreviation for half

45. Converting Systems • Why converting between systems is needed in health care • Common equivalencies between systems • Equivalencies frequently not exact • Steps to convert

46. Question • A patient reports that they drank 8 ounces (oz) of water. What is this in milliliters (mL)? • 80 mL • 120 mL • 240 mL

47. Answer • C. 240 mL • 1 oz = 30 mL • 8 oz = 240 mL

48. Temperature Conversion • Fahrenheit (F) used in U.S. • Celsius (C) used in Europe • Boiling point and freezing point comparisons • Converting between Celsius and Fahrenheit readings

49. Temperature Scales

50. Question • True or False: • 37 degrees C is a normal reading.