Example 1 from Algebra and Trigonometry, 13.5 Counting Principles

Using the Addition Principle

There are 2 vegetarian entrée options and 5 meat entrée options on a dinner menu. What is the total number of entrée options?

Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.

Solution
We can add the number of vegetarian options to the number of meat options to find the total number of entrée options.

There are 7 total options.

Your turn

The book's Try It right after this example: same idea, new numbers. Only the answer is given.

A student is shopping for a new computer. He is deciding among 3 desktop computers and 4 laptop computers. What is the total number of computer options?

How did it go?

Solution

Your turn

Solution

Your turn