Addition rules of Probability

P(Freshman or Pizza):

• 27/50
• 4/50
• 3/50
• 30/50

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?

• $\frac{4}{5}$

• $\frac{3}{5}$

• $\frac{1}{5}$

• $\frac{3}{20}$

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

• $\frac{1}{6}$

• $\frac{1}{3}$

• $\frac{2}{3}$

• $\frac{5}{6}$

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?

• $\frac{1}{12}$

• $\frac{1}{6}$

• $\frac{1}{4}$

• $\frac{11}{36}$

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?

• $\frac{419}{540}$

• $\frac{119}{180}$

• $\frac{197}{540}$

• $\frac{38}{135}$

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?

• $\frac{19}{120}$

• $\frac{29}{120}$

• $\frac{39}{120}$

• $\frac{49}{120}$

A seven-sided number cube with sides numbered 1, 2, 3, 4, 5, 6, 7 is rolled. What is the probability that a 4 or an odd number is rolled?

• $\frac{4}{49}$

• $\frac{2}{7}$

• $\frac{3}{7}$

• $\frac{5}{7}$

A seven-sided number cube with sides numbered 1, 2, 3, 4, 5, 6, 7 is rolled. What is the probability that an odd number or a seven is rolled?

• $\frac{4}{49}$

• $\frac{3}{7}$

• $\frac{4}{7}$

• $\frac{14}{15}$

If you roll one die, what is the probability of getting an even number or a multiple of 3?

• 1/3
• 2/3
• 1/2
• 1/6

find the probability of choosing a student at random that plays an instrument OR a sport

• 1/2
• 13/20
• 21/20
• 4/5