Math Skills

rounding rules

standard guidelines for changing a number into an approximation

capacity

the measure of how much matter can fit in a given area

decimals

a way to write fractions using a decimal point

What is the temperature of an autoclave set at 250ºF? a. 121ºC b. 139ºC c. 160ºC d. 450ºC

a. 121ºC

The following two rules are helpful when making approximations:

- When the number to the right of the digit being rounded is five or greater, the number is rounded up. For example, if 68 is being rounded to the nearest 10, it rounds to 70. - When the number to the right of the one being rounded is four or less, the number is rounded down. For example, if 23 is being rounded to the nearest 10, it rounds to 20.

To make the most accurate estimations and approximations:

- base an estimation on the largest possible sample size. - use research and the prior experience of others to support an estimation. - follow rounding rules correctly to make approximations.

Situations where healthcare workers use basic math skills:

- counting pills - calculating dosages of medication - ordering the correct amount of medical supplies - adding up the nutrients consumed by a patient - calculating body mass index (BMI) - interpreting lab test results

Which of the following are basic arithmetic operations that may be used in a healthcare job? Select all that apply. a. subtracting b. multiplication c. factoring equations

a and b

arithmetic

a branch of mathematics that deals with rational numbers

improper fraction

a fraction in which the numerator is larger than the denominator

In the healthcare setting, you will probably encounter the following units:

- 1000 kilo- - 10 deka - the base unit (no prefix) - 00.1 deci- - 0.01 centi- - 0.001 milli- - 0.00000 micro- (µ)

Arithmetic includes math's most basic functions:

- addition - subtraction - multiplication - division

conversion factor

a ratio or expression used to change a number from one system into another

approximation

a rounded number

metric system

a standardized system of measurement that uses base units and prefixes to indicate values

clinical trial

a test in which a new drug or procedure is used on a group of patients who have a similar condition

A patient weighs 70 kg. The medication must be delivered at a dosage of 15 mg per 10 kg of body weight. What is the correct dose of the medication? a. 70 mg b. 85 mg c. 105 mg d. 1,050 mg

c. 105 mg

A patient checks in at the emergency room concerned that she has lost too much weight suddenly. She says her weight used to be 64 kg. How much did she used to weigh in pounds? Round your answer to the nearest pound. a. 30 lbs. b. 67 lbs. c. 141 lbs. d. 173 lbs.

c. 141 lbs. - To convert from kilograms to pounds, remember that 1 kg = 2.2 lbs. 64 kg x (2.2 lbs./ 1 kg) = 141 lbs.

A patient at the hospital is 63 inches tall. How many centimeters tall is the patient? a. 24 b. 102 c. 160 d. 171

c. 160

Reduce the following improper fraction into a proper fraction: 14/6 a. 7/3 b. 1 4/6 c. 2 1/3 d. 2 2/6

c. 2 1/3

Decimals can also be expressed as: a. only fractions b. only percentages c. fractions or percentages d. none of the above

c. fractions or percentages

A patient comes into the emergency room just five minutes before midnight. The admitting nurse writes that the patient arrived at _____________. a. 11:55 b. 12:05 c. 12:55 d. 23:55

d. 23:55

A medical assistant needs to move a 15 kg box of supplies. How many pounds does the box weigh? a. 7 lbs. b. 13 lbs. c. 26 lbs. d. 33 lbs.

d. 33 lbs.

854 rounded to the nearest hundred is _____________. a. 800 b. 850 c. 860 d. 900

d. 900

rational numbers

numbers that can be written as ratios, or fractions

reducing a fraction

the act of simplifying a fraction so it has the smallest possible numerator and denominator

sample size

the number of people tested during a clinical trial

proper fraction

a fraction in which the numerator is smaller than the denominator

estimation

a prediction of a numerical value based on the evidence that is available

fraction

a ratio of two numbers

There are __________ milliliters in one liter. a. 10 b. 100 c. 1000

c. 1000

Which of the following units of measure are used in the metric system? a. liter b. ounce c. gram d. meter e. degrees Fahrenheit

a, c, and d

Five out of twenty patients Nurse B is caring for require hourly visits. What fraction of patients does Nurse B need to visit every hour? Choose the most reduced answer. a. 1/4 b. 1/5 c. 5/5 d. 5/20

a. 1/4

Which of the following are proper fractions? Check all that apply. a. 5/3 b. 1/8 c. 4/5 d. 10/7

b and c

In which situation might a healthcare worker make an estimation? Check all that apply. a. weighing a patient on a scale b. predicting patient recovery time c. counting pills to put into a pill bottle d. judging which size blood pressure cuff will fit a patient's arm

b and d

Which fractions are equivalent to 0.5? a. 3/9 b. 1/2 c. 1/5 d. 5/10

b and d

12 rounded to the nearest ten is _______________. a. 5 b. 10 c. 15 d. 20

b. 10

There are ________ centimeters in one meter. a. 10 b. 100 c. 1000

b. 100

A nurse delivers medication to a patient at 6:10 in the evening. How does the nurse record this time in the patient's chart? a. 6:10 b. 18:10 c. 6:10 p.m. d. 18:10 p.m.

b. 18:10 - To convert to the twenty-four-hour clock, add 12 to 6, then count the minutes. 12 + 6 = 18 It was 10 minutes after 6. Therefore, the time was 18:10.

Nurse A needs to give a patient 0.6 g of medication. The medication comes in tablets of 0.2 g. How many tablets must Nurse A get? a. 2 b. 3 c. 6 d. 12

b. 3

The doctor has asked that a patient's medication be reduced by 25%. The patient is currently taking 400 mg of medication per day. How much medication will the patient receive moving forward? a. 100 mg b. 300 mg c. 375 mg d. 425 mg

b. 300 mg

A coast guard medic arrives on the scene of a capsized boat. The medic finds a patient who has been adrift in cold water for several hours. The patient's body temperature is 94ºF. What is the patient's body temperature in Celsius? a. 14ºC b. 34ºC c. 70ºC d. 112ºC

b. 34ºC - Remember the conversion factor: 94°F - 32 x 5/9 = 34°C Also, you can check your answer by judging its reasonableness. Degrees Celsius is much lower than degrees Fahrenheit; therefore if you got a number at or above 94°, you know you calculated incorrectly.

A patient with insomnia reports staying awake for 34 hours and 45 minutes before finally falling asleep. The nurse writes that the patient was continuously awake for approximately hours. a. 34 b. 35 c. 45 d. 50

b. 35

A nurse is asked to administer a liquid medication to a patient. The medication must be at body temperature. The temperature of which of the following containers is the best choice to deliver the medication to the patient? a. 25ºC b. 37ºC c. 48ºC d. 98.6ºC

b. 37ºC

A nurse does not have a calculator and has to quickly determine how many 19 mg dosages are needed for 31 people. Approximately how many milligrams should the nurse get from the pharmacy? a. 50 mg b. 600 mg c. 3,000 mg

b. 600 mg

An elderly patient goes missing at 9:00 in the morning and is not found until 17:30. How many hours was the patient missing? a. 8 minutes and 30 seconds b. 8 hours and 30 minutes c. 12 hours and 30 minutes d. 12 minutes and 30 seconds

b. 8 hours and 30 minutes

854 rounded to the nearest ten is _____________. a. 800 b. 850 c. 860 d. 900

b. 850

A 0.09 mg/L IV solution = a. 0.9% b. 9% c. 90% d. 900%

b. 9% - One way to convert a decimal to a percentage is to move the decimal over two places to the right and then add the % symbol.

The prefix meaning one millionth of a gram is _________. a. deka b. micro c. milli d. kilo

b. micro

In a hospital, a doctor would record times on a patient chart using the _______________ clock. a. twelve-hour b. twenty-four-hour

b. twenty-four-hour

When would a healthcare worker need to use basic arithmetic? Check all that apply. a. measuring height b. recording a patient's age c. ordering medical supplies d. calculating medication dosage

c and d - Many healthcare workers use basic arithmetic on a daily basis such as adding, subtracting, multiplying, and dividing.

A nurse measures a patient's waist size as 120 cm. How many mm is this? a. 12 mm b. 120 mm c. 1,200 mm d. 12,000 mm

c. 1,200 mm - 1 cm = 10 mm Therefore, move the decimal one place (count the number of zeroes). The decimal moves to the right since the problem focuses on converting from a larger unit of measure to a smaller one.