Probability General Addition Rule

Amanda spins a spinner numbered 1 to 10. What is the probability that the spinner lands on an odd number or a number that is divisible by 3?

A group of 5 men and 5 women are applying for two job positions. Each of the 10 job candidates has the same chance of receiving a job offer. What is the probability that the company will hire a man or a woman for each of the two positions?

Using the spinner, what is the probability of spinning purple or green?

The outcomes for rolling two number cubes numbered 1 through 6 are shown above. What is the probability the sum of the number cubes will be 7 or 4?

Thirty-two percent of families residing in a rural, farming town own a goat and 41% of families own a dog. Twenty-four percent of families own both types of animals. If a family from this town is chosen at random, what is the probability that it owns either a goat or a dog?

• 0.15

• 0.33

• 0.49

• 0.97

A total of 540 customers, who frequented an ice cream shop, responded to a survey asking if they preferred chocolate or vanilla ice cream.

308 of the customers preferred chocolate ice cream.

263 of the customers were female.

152 of the customers were males who preferred vanilla ice cream.

What is the probability that a customer chosen at random is a male or prefers vanilla ice cream?

A box contains 18 blue flashlights, 3 red flashlights, 7 silver flashlights, and 2 black flashlights. The flashlights are identical in size and shape. If one flashlight is chosen at random, what is the probability that the flashlight will be either blue or black?

The probability that Flight 9876 will be late is 0.27. The probability that Flight 123 will be late is 0.11. The probability that both flights will be late is 0.09. What is the probability that Flight 9876 or Flight 123 will be late?

• 0.47

• 0.38

• 0.29

• 0.07

Based on past experiences, Miss Olenik knows that 1/5 of the mistakes on the essays she grades are grammar mistakes, 1/8 of the mistakes are spelling mistakes, and 1/12 of the mistakes are both grammar and spelling mistakes. If an essay is selected at random, what is the probability that the essay contains a grammar mistake or a spelling mistake?

To win a prize in a game, a player must throw a ball into a basket or kick a ball through a goal.

• The probability that the player will throw the ball into the basket is 0.30.

• The probability that the player will kick the ball through the goal is 0.20.

• The probability that the player will throw the ball into a basket and kick the ball through the goal is 0.06.

What is the probability that the player will either throw the ball into the basket or kick the ball through the goal, but NOT both?

• 0.04

• 0.44

• 0.50

• 0.56