Probability Theory for Nursing: Online Quizzes and Practice Tests

Question 1

What is the correct definition of odds?

Accepted Answer

The probability of an event occurring expressed as a ratio.

Answer

The probability of an event not occurring expressed as a percentage.

Answer

A measure of likelihood that is interchangeable with probability.

Question 2

In a study of patient outcomes, the probability of a successful outcome is 0.7. What is the probability of an unsuccessful outcome?

Accepted Answer

0.3

Answer

0.5

Answer

0.7

Answer

1

Question 3

In a standard deck of 52 playing cards, what is the probability of randomly drawing a Queen?

Accepted Answer

1/13

Answer

1/4

Question 4

Which characteristic is **NOT** associated with a normal distribution?

Accepted Answer

Skewed to one side

Answer

Symmetrical around the mean

Answer

Bell-shaped

Answer

Single mode

Question 5

In a hospital emergency department, which probability distribution is most appropriate for modeling the number of patients admitted per hour?

Accepted Answer

Poisson distribution

Answer

Binomial distribution

Answer

Normal distribution

Question 6

Which of the following is not a measure of central tendency?

Accepted Answer

Standard deviation

Answer

Mean

Answer

Median

Answer

Mode

Question 7

In a group of patients who underwent surgery, what is the likelihood that a randomly selected patient will experience post-operative pain?

Accepted Answer

The probability can be estimated from available data on post-operative pain.

Answer

The probability is unknown.

Answer

The probability is always 50%.

Question 8

From a standard deck of cards, what is the likelihood of drawing the red suit?

Accepted Answer

1 in 4

Answer

1 in 13

Answer

1 in 2

Answer

1 in 52

Question 9

A patient facing a medical procedure has a 30% chance of developing a complication. What is the probability that the patient will avoid complications?

Accepted Answer

70%

Answer

30%

Answer

50%

Answer

100%

Question 10

Which probability distribution quantifies the number of successes in a sequence of independent experiments?

Accepted Answer

Binomial distribution

Answer

Normal distribution

Answer

Poisson distribution

Answer

Uniform distribution

Question 11

What is the primary purpose of Bayes' theorem?

Accepted Answer

Calculating the probability of an event based on new evidence

Answer

Determining the probability of independent events occurring

Answer

Predicting future outcomes of random processes

Answer

Estimating parameters of a probability distribution

Question 12

A diagnostic test has a sensitivity of 90% and a specificity of 85%. If the disease prevalence is 10%, what is the probability that a person who tests positive actually has the disease?

Accepted Answer

14.3%

Answer

52.9%

Answer

85.0%

Answer

90.0%

Question 13

Which assumption is fundamental to probability theory?

Accepted Answer

Event probabilities range from 0 to 1

Answer

Events are independent

Answer

Sample size must be large

Answer

Outcomes of experiments are always predictable

Question 14

Which probability distribution describes the probability of observing a specified number of successes in a series of independent trials?

Accepted Answer

Binomial distribution

Answer

Normal distribution

Answer

Poisson distribution

Answer

Exponential distribution

Question 15

Given that the probability of event A occurring is 0.4 and the probability of event B occurring is 0.6, what is the probability of both events occurring?

Accepted Answer

0.24

Answer

0.1

Answer

0.6

Answer

0.4

Question 16

Bayes' theorem is used to determine:

Accepted Answer

The probability of an event based on the occurrence of another event

Answer

The probability of an event without considering other events

Answer

The average value of a distribution

Answer

The variation of a distribution

Question 17

Which of the following is an example of a continuous probability distribution?

Accepted Answer

Normal distribution

Answer

Binomial distribution

Answer

Poisson distribution

Answer

Hypergeometric distribution

Question 18

The mean of a distribution represents:

Accepted Answer

The average value of the distribution

Answer

The highest frequency outcome

Answer

The middle value of the distribution

Answer

The spread of the distribution

Question 19

What is the probability of selecting a red card from a deck of 52 standard playing cards?

Accepted Answer

1/13

Answer

1/4

Answer

1/2

Answer

1

Question 20

When rolling two fair six-sided dice, what is the probability of obtaining a sum of 7?

Accepted Answer

1/12

Answer

1/6

Answer

1/18

Answer

1/36

Question 21

In a group of 10 patients, there are 6 male patients. What is the probability of randomly selecting a male patient from this group?

Accepted Answer

0.6

Answer

0.3

Answer

0.5

Answer

0.9

Question 22

Which formula represents Bayes' theorem?

Accepted Answer

P(A|B) = P(B|A) * P(A) / P(B)

Answer

P(A) = P(B|A) * P(A|B)

Answer

P(A and B) = P(A) * P(B)

Answer

P(A or B) = P(A) + P(B) - P(A and B)

Question 23

What is the probability of obtaining a z-score of -1.96 or less in a standard normal distribution?

Accepted Answer

0.025

Answer

0.05

Answer

0.1

Answer

0.95

Question 24

Which of the following is a key characteristic of probability distributions?

Accepted Answer

The sum of probabilities across all possible outcomes equals 1.

Answer

Probabilities can range from negative infinity to positive infinity.

Answer

The probability of an impossible event is less than 0.

Answer

The probability of an event that will definitely occur is greater than 1.

Question 25

In a healthcare setting, which of the following is an example of conditional probability?

Accepted Answer

The probability of a patient developing a specific disease given their family history.

Answer

The probability of a patient recovering from an illness within a certain time frame.

Answer

The probability of a patient taking their medication as prescribed.

Answer

The probability of a patient being admitted to the hospital for a specific condition.

Question 26

Bayes' theorem is primarily used to:

Accepted Answer

Calculate the probability of an event based on new or updated information.

Answer

Calculate the probability of multiple independent events occurring simultaneously.

Answer

Calculate the probability of an event occurring in the future based on past data.

Answer

Calculate the probability of an event given that another event has not occurred.

Question 27

Which of the following is a characteristic of a continuous probability distribution?

Accepted Answer

It can take on any value within a specified range.

Answer

It has a finite number of possible outcomes.

Answer

Its probability density function is a discrete function.

Answer

Its cumulative distribution function is a step function.

Question 28

The probability of an event that is certain to occur is:

Accepted Answer

1

Answer

0

Answer

0.5

Answer

Impossible to determine

Question 29

Which of the following is an example of a discrete probability distribution?

Accepted Answer

Binomial distribution

Answer

Uniform distribution

Answer

Normal distribution

Answer

Exponential distribution

Question 30

In a survey of 200 nurses, 120 were female. What is the probability of randomly selecting a male nurse?

Accepted Answer

0.2

Answer

0.5

Answer

0.6

Answer

0.8

Question 31

In the context of healthcare, which probability distribution is most relevant for modeling the number of patients arriving at a hospital per hour?

Accepted Answer

Poisson distribution

Answer

Binomial distribution

Answer

Normal distribution

Answer

Exponential distribution

Question 32

Which probability distribution models continuous random variables?

Accepted Answer

Normal distribution

Answer

Binomial distribution

Answer

Poisson distribution

Answer

Hypergeometric distribution

Question 33

From a deck of 52 cards with 13 red cards, what's the probability of drawing a red card?

Accepted Answer

1/4

Answer

1/5

Answer

1/13

Answer

1/52

Question 34

Define conditional probability.

Accepted Answer

The probability of an event given that another event has occurred.

Answer

The probability of two events occurring simultaneously.

Answer

The probability of an event occurring independently of any other event.

Answer

The probability of an event occurring after another event has occurred.

Question 35

Given a 'tails' on a coin flip, what's the probability of getting a 'heads' on the next flip?

Accepted Answer

1/2

Answer

1/4

Answer

3/4

Answer

0

Question 36

What's the probability of rolling '6' on a die three times in a row?

Accepted Answer

1/216

Answer

1/6

Answer

1/18

Answer

1/54

Question 37

The probability of an event occurring is defined as the:

Accepted Answer

Ratio of the number of outcomes in the event to the number of outcomes in the sample space

Answer

Average number of successes in a series of trials

Answer

Likelihood that an event will occur

Answer

Difference between the number of successes and the number of failures

Question 38

Which property of conditional probability states that it is always less than or equal to the unconditional probability?

Accepted Answer

True

Answer

False

Question 39

Which probability distribution is used to model the number of successes in a sequence of independent trials with constant probability of success?

Accepted Answer

Binomial distribution

Answer

Poisson distribution

Answer

Normal distribution

Answer

Exponential distribution

Question 40

If the mean of a binomial distribution is 5 and the probability of success is 0.4, what is the variance?

Accepted Answer

3.2

Answer

3

Answer

4

Answer

5

Question 41

A nurse is administering a medication to a patient with a 20% probability of experiencing side effects. What is the probability that the patient will not experience side effects?

Accepted Answer

80%

Answer

20%

Answer

50%

Answer

30%

Question 42

Select the answer choice that is NOT a defining characteristic of a probability distribution:

Accepted Answer

Probabilities can be negative

Answer

The sum of all probabilities must equal 1

Answer

Each probability is a positive value

Answer

The distribution describes all possible outcomes

Question 43

Determine the probability of rolling a 6 when using a fair six-sided die:

Accepted Answer

1/6

Answer

1/2

Answer

1/3

Answer

1/4

Question 44

A deck of cards contains 52 cards. If the first card drawn is a spade, calculate the probability of drawing a heart next:

Accepted Answer

1/51

Answer

1/13

Answer

1/26

Answer

1/102

Question 45

Which of the following is NOT an assumption required for Bayes' Theorem to be applicable?

Accepted Answer

The events are independent

Answer

The events are mutually exclusive

Answer

The probabilities of the events are accurately known

Answer

The events are exhaustive

Question 46

In a medical context, Bayes' Theorem can be used to calculate which probability?

Accepted Answer

P(Disease | Positive Test)

Answer

P(Positive Test | Disease)

Answer

P(Disease) / P(Positive Test)

Answer

P(Positive Test) / P(Disease)

Question 47

Which probability distribution type is the Normal distribution an example of?

Accepted Answer

Continuous

Answer

Discrete

Answer

Binomial

Answer

Geometric

Question 48

Calculate the expected value of a uniform probability distribution defined over the interval [0, 1]:

Accepted Answer

0.5

Answer

0

Answer

1

Answer

Cannot be determined

Question 49

Which statement accurately defines the complement of the event 'the patient recovers from surgery'?

Accepted Answer

The patient does not recover from surgery

Answer

The patient undergoes a successful surgery

Answer

The patient experiences complications during surgery

Answer

The patient passes away during surgery

Question 50

In the context of probability, two events, A and B, are considered independent if:

Accepted Answer

The occurrence of one event has no impact on the likelihood of the other event occurring

Answer

The occurrence of one event affects the likelihood of the other event occurring

Answer

The events are mutually exclusive

Answer

The probability of both events occurring simultaneously equals the sum of their individual probabilities

Question 51

What is a fundamental limitation of probability theory?

Accepted Answer

It cannot offer definitive predictions about future events

Answer

It assumes that all possible outcomes are equally probable

Answer

It is overly complex for practical applications

Answer

It is only applicable to events with discrete outcomes

Question 52

From a deck of 52 cards, what is the probability of drawing a heart?

Accepted Answer

1/13

Answer

4/52

Answer

13/52

Answer

1/4

Question 53

Which of the following probability distributions is used to model continuous random variables?

Accepted Answer

Normal distribution

Answer

Hypergeometric distribution

Answer

Poisson distribution

Answer

Binomial distribution

Question 54

A study estimates that the probability of a patient recovering from a certain illness is 0.8. If 100 patients are infected with the illness, what is the expected number of patients who will recover?

Accepted Answer

80

Answer

100

Answer

50

Answer

20

Question 55

Which of the following is NOT a property of probability?

Accepted Answer

Probability can have a negative value.

Answer

Probability values range between 0 and 1.

Answer

The sum of probabilities of all possible outcomes is 1.

Answer

For independent events, the probability of their joint occurrence is the product of their individual probabilities.

Question 56

Bayes' theorem is primarily used for:

Accepted Answer

Updating probabilities based on new evidence or information.

Answer

Calculating probabilities of mutually exclusive events.

Answer

Finding the standard deviation of a probability distribution.

Answer

Determining the mean of a random variable.

Question 57

To calculate the probability of an event B occurring given that event A has already occurred, which formula should be used?

Accepted Answer

P(B|A) = P(A and B) / P(A)

Answer

P(B|A) = P(A) / P(B)

Answer

P(B|A) = P(B) + P(A)

Question 58

Which of the following scenarios best represents a mutually exclusive event?

Accepted Answer

Drawing a red card from a deck of cards without replacement.

Answer

Rolling an even number on a six-sided die.

Answer

Getting a fever and a headache simultaneously.

Answer

Selecting a female student from a class of 20 students.

Question 59

When flipping a fair coin twice, what is the probability of getting at least one tail?

Accepted Answer

3/4

Answer

1/2

Answer

1/4

Answer

1

Question 60

The probability of an event that is sure to happen is:

Accepted Answer

1

Answer

0

Answer

Cannot be determined

Answer

0.5

Question 61

Independent events are defined as:

Accepted Answer

The outcome of one event does not affect the probability of the other event.

Answer

The outcome of one event decreases the probability of the other event.

Answer

The outcome of one event increases the probability of the other event.

Question 62

In a deck of 52 cards, what is the probability of selecting a red card?

Accepted Answer

1/2

Answer

Cannot be determined

Answer

1/4

Answer

1/13

Question 63

A key assumption of Bayes' theorem is that:

Accepted Answer

All possible outcomes are mutually exclusive and exhaustive.

Answer

The probability of an event is constant over time.

Answer

The order of events is significant

Question 64

A hospital has a 5% rate of surgical infections. If a patient undergoes three independent surgeries, what is the probability of experiencing at least one infection?

Accepted Answer

0.141

Answer

0.25

Answer

0.05

Answer

0.95