Q: A probability experiment consists of flipping a fair coin. What is the sample space for this experiment?

$$S = \{\text{Head}, \text{Tail}\}$$

Q: A four-digit access code uses digits 0-9, and each digit can be used only once. How many possible codes are there?

$$10 \times 9 \times 8 \times 7 = 5040$$

Q: A four-digit access code uses digits 0-9, digits can be repeated, but the first digit cannot be 0 or 1. How many possible codes are there?

$$8 \times 10 \times 10 \times 10 = 8000$$

Question 1

A probability experiment consists of flipping a fair coin. What is the sample space for this experiment?

Accepted Answer

$$S = \{	ext{Head}, 	ext{Tail}\}$$

Question 2

You roll a six-sided die. Event A is rolling a 2. Is this a simple event?

Accepted Answer

Yes, because it consists of only one outcome.

Question 3

A survey asks for blood type (O, A, B, AB) and Rh factor (+ or -). How many possible outcomes are in the sample space?

Accepted Answer

$$4 	imes 2 = 8$$

Question 4

If a car can be chosen from 3 manufacturers, 2 sizes, and 4 colors, how many different car choices are possible?

Accepted Answer

$$3 	imes 2 	imes 4 = 24$$

Question 5

An access code consists of 4 digits, each from 0 to 9, and digits can be repeated. How many possible codes are there?

Accepted Answer

$$10^4 = 10$$,000$$

Question 6

What is the classical probability of rolling a number less than 5 on a fair six-sided die?

Accepted Answer

$$\frac{4}{6} = 0.667$$

Question 7

A company surveys 1490 adults. 578 read only print books. What is the empirical probability that the next adult reads only print books?

Accepted Answer

$$\frac{578}{1490} \approx 0.388$$

Question 8

Which of the following is an example of subjective probability?

Accepted Answer

A doctor estimates a 90% chance of full recovery for a patient.

Question 9

What is the probability of the complement of an event E, given $$P(E) = 0.4$$?

Accepted Answer

$$P(E') = 1 - 0.4 = 0.6$$

Question 10

A probability experiment consists of tossing a coin and spinning a spinner numbered 1 to 8. What is the probability of tossing a tail and spinning an odd number?

Accepted Answer

$$\frac{4}{16} = 0.25$$

Question 11

Which statement best describes the Law of Large Numbers?

Accepted Answer

As an experiment is repeated, the empirical probability approaches the theoretical probability.

Question 12

A college ID number consists of 8 digits (0-9), each digit can be repeated. What is the probability of randomly generating your own ID number?

Accepted Answer

$$\frac{1}{100,000,000}$$

Question 13

Which of the following is NOT a valid probability value?

Accepted Answer

1.2

Question 14

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

Accepted Answer

The event is impossible.

Question 15

A raffle has 1000 tickets and you buy one. What type of probability is used to determine your chance of winning?

Accepted Answer

Classical probability

Question 16

A student claims the probability of getting an A on the next test is 0.9, based on their feeling. What type of probability is this?

Accepted Answer

Subjective probability

Question 17

If you roll a six-sided die, what is the probability of rolling a 7?

Accepted Answer

$$0$$

Question 18

A survey finds that 395 out of 1490 adults read no books last year. What is the probability that a randomly selected adult read at least one book?

Accepted Answer

$$1 - \frac{395}{1490} = 0.735$$

Question 19

A four-digit access code uses digits 0-9, and each digit can be used only once. How many possible codes are there?

Accepted Answer

$$10 	imes 9 	imes 8 	imes 7 = 5040$$

Question 20

A four-digit access code uses digits 0-9, digits can be repeated, but the first digit cannot be 0 or 1. How many possible codes are there?

Accepted Answer

$$8 	imes 10 	imes 10 	imes 10 = 8000$$

Chapter 3: Probability – Basic Concepts and Counting Principles

Study Guide - Practice Questions

Study Guide - Flashcards