Basic Probability & Mutually Exclusive

Which of the following is always true for probabilities?

• They must be between 0 and 1.

• They can be larger than 1.

• They can be negative.

• They must equal 1/2.

How many outcomes are in the sample space when you flip a coin then roll a fair die? (draw a tree diagram to help).

• 6

• 8

• 12

• 16

A die is rolled once. What is the probability of not rolling 6? (Give answers to 3 decimals.)

• 0.167

• 0.833

• 0.667

• 0.333

A spinner has 5 equal sections: 2 yellow, 1 red, 1 green, 1 blue. What is the probability of landing on red or blue?

• 0.200

• 0.400

• 0.600

• 0.800

A bag has 6 marbles: 2 red, 3 blue, 1 green. What is probability a blue marble is not chosen?

• 0.500

• 0.333

• 0.667

• 0.833

A coin lands heads 10 times in a row. What is probability of landing on heads on the 11th flip of a fair coin?

• 0.000

• 1.000

• 0.500

• 0.600

Which is a simple event?

• Rolling a 4 on one die

• Rolling at least a 5 on one die

Which pair of events is mutually exclusive on a fair die?

• Rolling an odd number or a prime number

• Rolling a 5 or an even number

• Rolling a number > 3 or an even number

• Rolling a multiple of 3 or an even number

At CHS, 150 students: 70 students are in drama, 40 are in student council, and 12 are in both. What is the probability that a randomly chosen student is in drama or student council?

• 0.733

• 0.573

• 0.653

• 0.813

Two dice are rolled. What is probability they sum to 7?

• 0.083

• 0.111

• 0.125

• 0.167