# Complement of an Event Worksheets

What is a Complement of an Event? When developing probability concepts, it is essential to understand all terms and phrases that are frequently used in probability problems. Events, sample space, outcomes, order, and complement of an event. Complement is a term that is not only used in probability but is also part of the concept of sets. Whether the term is being used in sets or probability, it holds the same meaning. When you are asked to use a complement of the set, it means all elements that are not part of the set. In probability, when we talk about the complement of an event, it includes all outcomes other than the required or desired outcomes. If we write a probability of the desired event we use the following symbols; P(A) and to denote a complement of the event, we write P(A'). When you add these two elements, the result is 1.

• ### Basic Lesson

Introduces the concept of how to algebraic workout events that complement each other. A single card is chosen at random from a standard deck of 52 playing cards. What is the probability of choosing a card that is not a king?

• ### Intermediate Lesson

This lesson focuses on using probability focus equations to solve complements. A glass jar contains 20 red marbles. If a marble is chosen at random from the jar, what is the probability that it is not red?

• ### Independent Practice 1

Students practice with 20 Complement of an Event problems. The answers can be found below. A spinner has 4 equal sectors colored yellow, blue, green and red. What is the probability of landing on a sector that is not yellow after spinning this spinner?

• ### Independent Practice 2

Another 20 Complement of an Event problems. The answers can be found below.

• ### Homework Worksheet

Reviews all skills in the unit. A great take home sheet. Also provides a practice problem.

• ### Skill Quiz

10 problems that test your ability to find the probability of the complement of an event.

• ### Homework and Quiz Answer Key

Answers for the homework and quiz.