1. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Chapter 5 Medical Math

2. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Importance of Math Frequently used in health care Requires 100 percent accuracy Errors can have dire consequences

3. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Math Anxiety Common problem Impedes performance Can be overcome False beliefs versus reality

4. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Question True or False: –If a person currently has problems with math, it can be assumed that it will always be a problem.

5. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Answer False Math anxiety –Learned behavior –Can be overcome

6. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Basic Calculations Whole numbers –Add –Subtract –Multiply –Divide

7. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Decimals Expressed in units of ten Placement values Zero used before decimal point if number begins to right of decimal point

8. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Working with Decimals Placement of decimal –Add –Subtract –Multiply –Divide

9. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Fractions Represents part of a whole Numerator Denominator

10. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Working with Fractions Add Subtract Multiply Divide Improper fractions Reducing fractions

11. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Percentages Expresses whole or part of a whole Whole expressed as 100 percent Convert to decimal –Then perform calculation

12. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Ratios Show relationships between numbers or like values Compare presence of one value to another Frequently used to express strength of solution

13. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Converting Decimals, Fractions, and Percentages Decimal to fraction Decimal to percentage Fraction to decimal Fraction to percentage

14. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Converting Decimals, Fractions, and Percentages Percentage to decimal Percentage to fraction Percentage to ratio Ratio to percentage

15. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Question True or False: –¾, 75%, and 0.75 are all equivalent.

16. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Answer True ¾ –Fraction –If converted to percentage = 75% –If converted to decimal = 0.75

17. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Rounding Numbers What does it mean? –Round up –Round down

18. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Question What is 2.346 rounded to the nearest tenth? A.2 B.2.3 C.2.35

19. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Solving with Proportions Statement of equality between two ratios Used for converting from one unit to another Steps for solving problems

21. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Estimating Anticipate results Determine if answer is reasonable Calculate approximate answer

22. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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? A.½ tablet B.2 tablets C.4 tablets

23. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Military Time 24-hour clock No AM or PM Avoids errors 12 th hour = noon 24 th hour = midnight

25. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Question True or False: –The military time of 1600 is the same as 6 p.m. traditional time.

26. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Answer False 1600 = 4 p.m. 6 p.m. would be 1800 military time

27. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Military Clock

28. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Roman Numerals Arabic versus Roman numerals All numbers from seven key numerals –I, V, X, L, C, D, and M

29. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Question How would 43 be written in Roman numerals? A.XLIII B.XXXXIII C.XXXI

31. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Answer A. XLIII XLIII = 43 XXXXIII incorrect –Same numeral cannot be placed next to itself more than three times XXXI = 31

32. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Angles Comparison to reference plane Using angles in health care Measured in units –Degrees

33. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Angles

34. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Systems of Measurement Three systems –Distance Length –Capacity Volume –Mass Weight

35. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Systems of Measurement Nomenclature –Method of naming Need to convert between systems

36. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Household System Used in U.S. Nomenclature for distance/length Nomenclature for capacity/volume Nomenclature for mass/weight Common equivalents How to convert

37. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Question Which of the following is a capacity/volume unit in the household system? A.Inch B.Pound C.Ounce

38. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Answer C. Ounce Ounce –Unit of measurement for capacity/volume in household system –Also unit of measurement for mass/weight

39. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Answer C. Ounce Inch –Measurement for distance/length Pound –Measurement for mass/weight

40. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Metric System Used in Europe More accurate Easier to use Based on unit of ten Convert units by moving decimal Common prefixes

41. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Metric System Nomenclature for distance/length Nomenclature for capacity/volume Nomenclature for mass/weight

42. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Question How many centimeters are there in one meter? A.10 B.100 C.1000

43. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Answer B. 100 Meter –Base unit for distance/length in metric system –Centi = 1/100 –1 meter = 100 centimeters

44. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Converting Systems Why converting between systems is needed in health care Common equivalencies between systems Equivalencies frequently not exact Steps to convert

46. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Question A patient reports that they drank 8 ounces (oz) of water. What is this in milliliters (mL)? A.80 mL B.120 mL C.240 mL

47. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Answer C. 240 mL 1 oz = 30 mL –8 oz = 240 mL

48. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. 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. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Temperature Scales

50. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Question True or False: –37 degrees C is a normal reading.

51. © 2012 Cengage Learning. All Rights Reserved. May not be scanned, copied, duplicated, or posted to a publicly accessible website, in whole or in part. Answer True 37 degrees C = 98.6 degrees F –Normal reading