Q: Which formula represents the classical approach to probability for an event A?

$$P(A) = \frac{\text{number of ways A occurs}}{\text{number of different simple events}}$$

Q: Which of the following best describes a significantly low number of successes in a probability experiment?

If $$P(x \text{ or fewer}) \leq 0.05$$

Question 1

Which of the following best describes a simple event in probability?

Accepted Answer

An outcome or event that cannot be further broken down into simpler components.

Question 2

Given three births, which of the following is NOT a simple event?

Accepted Answer

The event '2 girls and 1 boy'.

Question 3

Which formula represents the classical approach to probability for an event A?

Accepted Answer

$$P(A) = \frac{	ext{number of ways A occurs}}{	ext{number of different simple events}}$$

Question 4

A survey found that 366 out of 2003 adults said they have seen a ghost. What is the probability that a randomly selected adult from this group has seen a ghost? (Round to three decimal places.)

Accepted Answer

$$0.183$$

Question 5

Which of the following is TRUE about the probability of an event?

Accepted Answer

It is always a value between 0 and 1, inclusive.

Question 6

If the probability of an event A is $$0.001$$, how would you interpret this probability?

Accepted Answer

Event A is very unlikely to occur.

Question 7

Which of the following is the correct formula for the complement of event A?

Accepted Answer

$$P(\bar{A}) = 1 - P(A)$$

Question 8

A roulette wheel has 38 slots. If you bet on the number 13, what are the actual odds against winning?

Accepted Answer

$$37:1$$

Question 9

If the probability of an event A is $$0.05$$, which of the following best describes the likelihood of A?

Accepted Answer

Unlikely

Question 10

Which approach to probability is used when you estimate the probability of rain tomorrow based on weather patterns and expert knowledge?

Accepted Answer

Subjective probability

Question 11

A simulation is most useful when:

Accepted Answer

None of the three common approaches to probability can be used.

Question 12

If the probability of an event A is $$0.7$$, what are the actual odds in favor of A?

Accepted Answer

$$0.7:0.3$$

Question 13

A medical test for a rare disease has a probability of $$0.02 of a $$positive result in healthy individuals. If a healthy person tests positive, is this result significantly high?

Accepted Answer

Yes, because $$0.02 \leq 0.05$$

Question 14

If you conduct an experiment 100 times and event B occurs 25 times, what is the relative frequency probability of event B?

Accepted Answer

$$P(B) = \frac{25}{100} = 0.25$$

Question 15

Which of the following best describes the sample space for rolling a single six-sided die?

Accepted Answer

{1, 2, 3, 4, 5, 6}

Question 16

If the probability of an event is 0, what does this mean?

Accepted Answer

The event is impossible.

Question 17

A casino offers a payoff of 35:1 for a bet with actual odds against of 37:1. If you bet $5 and win, what is your net profit?

Accepted Answer

$$175$$

Question 18

Which of the following is NOT a requirement for using the classical approach to probability?

Accepted Answer

Historical data must be available.

Question 19

If $$P(A) = 0.4$$, what is $$P(\bar{A})$$?

Accepted Answer

$$0.6$$

Question 20

Which of the following best describes a significantly low number of successes in a probability experiment?

Accepted Answer

If $$P(x 	ext{ or fewer}) \leq 0.05$$

Chapter 4: Probability – Fundamental Concepts and Applications

Study Guide - Practice Questions

Study Guide - Flashcards