Q: Which of the following is the correct formula for calculating the probability of an event $$A$$?

$$P(A) = \frac{\text{number of occurrences of } A}{\text{total number of outcomes}}$$

Q: A door passcode uses four digits. The second digit must be 4. The last digit must be even. How many different passcodes are possible?

$$10 \times 1 \times 10 \times 5$$

Question 1

Which of the following best describes the Rare Event Rule for Inferential Statistics?

Accepted Answer

If, under a given assumption, the probability of an observed event is extremely small, then the assumption is probably not correct.

Question 2

A password consists of five different capital letters. How many unique passwords can be formed if each letter can be used only once?

Accepted Answer

$$\frac{26!}{21!}$$

Question 3

Which of the following numbers cannot represent a probability? Select all that apply.

Accepted Answer

$$1.11$$

Question 4

What is the probability of rolling a sum of 7 with two fair six-sided dice?

Accepted Answer

$$\frac{1}{6}$$

Question 5

Which of the following is the correct formula for calculating the probability of an event $$A$$?

Accepted Answer

$$P(A) = \frac{	ext{number of occurrences of } A}{	ext{total number of outcomes}}$$

Question 6

If you flip a coin, spin a spinner with 3 colors (red, green, blue), and flip another coin, how many possible outcomes are there?

Accepted Answer

$$8$$

Question 7

Which of the following best describes a simple event?

Accepted Answer

An event that cannot be broken down into simpler components.

Question 8

A door passcode uses four digits. The second digit must be 4. The last digit must be even. How many different passcodes are possible?

Accepted Answer

$$10 	imes 1 	imes 10 	imes 5$$

Question 9

Which of the following statements about probability is FALSE?

Accepted Answer

Probabilities can be negative if the event is unlikely.

Question 10

How many different ways can you select one manufacturer (Ford, GM, Honda), one car size (compact, midsize), and one color (white, red, black, green)?

Accepted Answer

$$3 	imes 2 	imes 4 = 24$$

Question 11

Which of the following best describes classical probability?

Accepted Answer

Probability calculated when each event has an equal chance of occurring, without producing results.

Question 12

What is the value of $$5! ($$five factorial)?

Accepted Answer

$$120$$

Question 13

If you have 4 shirts, 3 pairs of pants, and 3 pairs of shoes, how many different outfits can you make (choosing one of each)?

Accepted Answer

$$4 	imes 3 	imes 3 = 36$$

Question 14

Which of the following is NOT a property of probability?

Accepted Answer

Probabilities can be greater than 1 for rare events.

Question 15

If you flip three coins, how many outcomes are in the sample space?

Accepted Answer

$$8$$

Question 16

Which of the following best describes the Fundamental Counting Principle?

Accepted Answer

Multiply the number of possible outcomes for each part of a procedure.

Question 17

Which of the following is the sample space for one roll of a six-sided die?

Accepted Answer

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

Question 18

Which of the following is an example of a dependent event?

Accepted Answer

Selecting a king from a deck, not replacing it, then selecting a queen.

Question 19

If you put 6 books on a shelf, in how many different ways can you arrange them?

Accepted Answer

$$6!$$

Question 20

Which of the following best describes the difference between classical and relative frequency probability?

Accepted Answer

Classical probability assumes all outcomes are equally likely and is calculated without experiments; relative frequency probability is based on observed data.

Introductory Statistics Chapter 4: Probability Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards