Q: You draw two cards from a standard deck of 52 cards without replacement. What is the probability that both are spades?

$$\frac{13}{52} \times \frac{12}{51}$$

Q: Airport inspectors found 102 defective scales out of 810. If two scales are randomly selected with replacement, what is the probability both are defective?

$$\frac{102}{810} \times \frac{102}{810}$$

Q: What is the formula for the addition rule for probability?

$$P(A \text{ or } B) = P(A) + P(B) - P(A \text{ and } B)$$

Question 1

Which of the following best describes a compound event?

Accepted Answer

An event that combines two or more simple events.

Question 2

A die with 8 sides is rolled. What is the probability of rolling a number less than 7?

Accepted Answer

$$\frac{6}{8}$$

Question 3

In a study, 3785 high school drivers texted while driving and 4720 did not. What is the probability that a randomly selected driver texted while driving?

Accepted Answer

$$\frac{3785}{8505}$$

Question 4

If the probability of event A is $$0.3$$, what is the probability of its complement $$A^c$$?

Accepted Answer

$$0.7$$

Question 5

What is the probability of not drawing a heart from a standard deck of 52 cards?

Accepted Answer

$$\frac{39}{52}$$

Question 6

A six-sided die is rolled. What is the probability of rolling a 5 or a 3?

Accepted Answer

$$\frac{2}{6}$$

Question 7

If events A and B are disjoint, which of the following is true?

Accepted Answer

$$P(A 	ext{ and } B) = 0$$

Question 8

You draw two cards from a standard deck of 52 cards without replacement. What is the probability that both are spades?

Accepted Answer

$$\frac{13}{52} 	imes \frac{12}{51}$$

Question 9

Airport inspectors found 102 defective scales out of 810. If two scales are randomly selected with replacement, what is the probability both are defective?

Accepted Answer

$$\frac{102}{810} 	imes \frac{102}{810}$$

Question 10

A survey asked subjects if they are members of an environmental group and if they are willing to pay higher prices. 28 were both members and willing, out of 1116 total. What is the probability a randomly selected subject is both?

Accepted Answer

$$\frac{28}{1116}$$

Question 11

What is the formula for the addition rule for probability?

Accepted Answer

$$P(A 	ext{ or } B) = P(A) + P(B) - P(A 	ext{ and } B)$$

Question 12

If events A and B are independent, what is $$P(A 	ext{ and } B)$$?

Accepted Answer

$$P(A) 	imes P(B)$$

Question 13

What is the probability of getting exactly two tails in three flips of a fair coin?

Accepted Answer

$$\frac{3}{8}$$

Question 14

In a disease test, 100 people with the disease tested positive, 35 tested negative. What is the sensitivity rate?

Accepted Answer

$$\frac{100}{135}$$

Question 15

What is the probability of drawing a king given that the card is red from a standard deck?

Accepted Answer

$$\frac{2}{26}$$

Question 16

If one person is randomly selected from 100 subjects, what is the probability they have type O blood given they are Rh-? (Rh- O: 6, total Rh-: 14)

Accepted Answer

$$\frac{6}{14}$$

Question 17

Which statement about the Law of Large Numbers is correct?

Accepted Answer

As a procedure is repeated, the relative frequency probability approaches the actual probability.

Question 18

A standard deck has 52 cards. What is the probability of selecting a king or a black card?

Accepted Answer

$$\frac{28}{52}$$

Question 19

If the probability of dying in a skydiving jump is $$0.000007$$, what is the probability of not dying?

Accepted Answer

$$1 - 0.000007 = 0.999993$$

Chapter 5: Probability – Foundations, Rules, and Applications

Study Guide - Practice Questions

Study Guide - Flashcards