7th Grade Math

Probability

PART A BCD

Get ConnectED

Multi-Part

Lesson 1

GLE 0706.5.5

Understand and apply basic

concepts of probability.

444 Probability and Predictions

Main Idea

Find the number of

permutations of a set

of objects and find

probabilities.

Vocabulary

permutation

combination

Permutations

How many different ways are there to arrange your first

three classes if they are math, science, and language arts?

Write math, science, and language arts on the index cards.

MATH SCIENCE LANGUAGE

ARTS

Find and record all arrangements of classes by changing

the order of the index cards.

1. When you first started to make your list, how many choices did
   you have for your first class?


2. Once your first class was selected, how many choices did you have
   for the second class? then, the third class?

A permutation is an arrangement, or listing, of objects in which order

is important. The arrangement of science, math, language arts is a

permutation of math, science, language arts because the order of the

classes is different.

You can use the Fundamental Counting Principle to find the number

of permutations.

Find a Permutation

SCHEDULES Find the number of possible arrangements of classes

in the Explore Activity. Use the Fundamental Counting Principle.

There are 3 choices for the first class.

There are 2 choices that remain for the second class.

There is 1 choice that remains for the third class.

the number of permutations of 3 classes

There are 6 possible arrangements, or permutations, of the 3 classes.

a. VOLLEYBALL In how many ways can the starting six players of

a volleyball team stand in a row for a picture?

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