Simple Probability and Complements

Simple Probability

Multiple Choice

P(even) =

• 5/7

• 1/7

• 2/7

• 4/7

Multiple Choice

P(NOT even) =

• 5/7

• 1/7

• 2/7

• 4/7

Multiple Choice

P(solid) =

• 1/5

• 4/5

• 3/5

• 2/5

Multiple Choice

P(NOT solid) =

• 1/5

• 4/5

• 3/5

• 2/5

​Simple Probability

​Ratio of desired outcomes to total number of outcomes.

​

​

​What is the probability of spinning an even number (as a fraction)?

Multiple Choice

A number cube is rolled. What is the probability of rolling a 6?

• 1/6

• 6/6

• 3/6

• 2/3

Multiple Choice

A number cube is rolled. What is the probability of rolling an odd number?

• 1/2

• 1/6

• 1/3

• 6/6

​Complement

The probability of an event not happening.

• ​Written as a ratio of undesired outcomes to total outcomes

​

​

​What is the complement of spinning a diamond?

Multiple Choice

What is the complement of choosing a marble with stripes?

The number on the left is what can not happen. The number on the right is the probability it can happen.

• 2/6 = 1/3

• 4/6 = 2/3

• 1/6

• 6/6 =1

Multiple Choice

The spinner shown is spun. What is the probability of not spinning a 6?

• 4/7

• 3/7

• 6/7

• 1/7

Multiple Choice

The formula for probability

• P=Favorable outcomes/total

• F=total outcomes/probability