Intro to Health Careers
Name
Ch 5 Medical Math
1. Applications of Math in Health Care p. 102
a.
b.
c.
d.
e.
f.
2. Math anxiety is a learned emotional reaction that can cause a mental block to learning
math, but the good news is that it can be
See Table 5-2 for tips on overcoming math anxiety, page 104
3. Health Care uses many basic math calculation, just to review:
a. Whole numbers are generally used for counting
b. When using decimals, always use a leading zero: 0.1, NOT just .1
But don’t use a trailing zero, 1 NOT 1.0
c. To avoid medication errors, avoid the unit cc, use mL for millimeters
d. Review Fractions
add ½ + ⅓ - =
multiply ⅔ x ¼ =
subtract ⅞ - ½ =
reduce
divide ⅓ ÷ ½ invert 2/1 =
Be sure to reduce the final answer to its simplest form
Use StudyWARE for practice
4. Percentages are used to express parts of a whole
: If a pizza is cut into 4 equal pieces, each slice is one fourth, or 25% of the whole pie 5. Ratios show relationships: Teacher to student ratio – 1:22
Nurse to patient ratio – 1:4
Bleach to water ratio – 1:10
Boys to girls ratio in your classroom today -
:
reduce
6. Health care workers need to be able to convert ratios to fractions to decimals to
percentages. For example 1 to 5, 1:5, 1/5, 0. to
%
7. Review rounding rules: less than 5, round down, 5 or greater, round up
87.5 rounds up to
26.3 rounds down to
8. Proportions are a statement of equality between 2 ratios, usually used to find an unknown
value. If 4:5 = 16:20 what is X? 4/5 = X/50, X =
To solve the problem, cross multiply, divide both sides by the number in front of the X to
find the solution.
Proportions are commonly used to convert unit of measure. Multiply the unknown by the
known ratio. 12 inches/1foot = 42 inch/X feet à 12X = 42 à
X = 42/12 which has a final answer of
9. Estimate to judge if your calculations are correct. Round to easy numbers to do mental
math. (It is a reasonable answer, in the right “ball park”, decimal in the right place)
10. Military time uses a 24 hour clock, no am or pm.
a. Convert 4:30pm to military time b. Convert 2:00am to military time c. Convert 1900 to traditional time d. Convert 0530 to traditional time 11. Roman Numerals are used in medications, ordering systems:
12. I=
IV=
XL=
V=
L=
IX=
XC=
X=
C=
XV=
D=
13. Re-write the Roman numeral into conventional numbers & vice versa: p.113
CXL
MCMXXXVII =
1139
94 =
14. Angles are measured in degrees (°)
a. What angles are used for what kind of injection? P.114
90°
b. 45°
M=
Systems of Measurement
15. Household system of measurement is used in American households for cooking. Health
care professionals need to know the equivalents in one system and between systems. The
most common and important follow:
16. Apothecary system: is the oldest and least used measurement system, still uses:
a. Grain is abbreviated as
, 1 of which =
mg
b. Drops is abbreviated as
, 15 of which =
ml
17. The Metric system (SI) uses multiples of ten for its different units. It is important to be
able to convert from metric to household, and household to metric.
18. 1 teaspoon =
ml,
1 ounce =
ml
19. 1 inch =
cm,
1 kilogram (kg) =
pounds (lbs)
20. Practice (see Skills USA Math sheet)
a. 45 inches =
cm round to whole cm =
b. 175 cm =
inches, =
ft,
inches, round to whole inches
c. 88 pounds =
kg, round to whole kg
d. 45 kg =
lbs
21. 1 : 4 ratio =
(fraction)
Decimal
=
22. Temperature Conversion from Fahrenheit (F) to Celsius (C)
a. Fraction Formula C to F if given C and want F
(°C x 9/5) + 32 = °F
Example: convert 10°C to F:
F to C if given F and want C
(°F – 32) x 5/9 = °C
b. Decimal formula in text page 120, and Use study WARE CD
Complete Ch 5 Workbook pages.
Complete Thermometer Work Sheet
Complete Infant Growth Chart
Complete Vital Sign Workbook pages: 20-1a,d,e, 20-2 & 20-4, 20-5
Complete Personal Health Literacy Project
%
Health Literacy
Name
Personal Health Data – Know your health numbers!
1. Resting Pulse - Count radial pulse for 15 seconds:
2. Respirations – (get a partner to count you)
X4=
bpm
X4=
3. Weight (without shoes)
pounds (divide by 2.2 for Kg)
4. Height (without shoes)
inches (X 2.54, then divide by 100) 1.
5. Waist circumference
inches, Hips in inches
6. Waist to Hip ratio:
waist in inches =
Hips in inches =
7. Body Mass Index BMI formula: Weight in KG =
Ht in (m)2
Your numbers (#7)
=
(
=
mx
m)
BMI
BMI Ranges
Under Weight
Healthy Weight
Over Weight
Obese
Less than 18.5
19-24.9
25-29.9
30 plus
8. Basal Metabolic Rate BMR (boys: 1 cal X kg X 24h)
(girls: 0.9 cal X kg X24h)
9. Activity level
1.3 average teen
1.5 active girl
1.6 active boy
10. Estimate daily Energy needs according to activity level
BMR x Activity Factor = calories needed per day
X
=
calories needed per day
To maintain weight