## CHAPTER 2: NUMERATION

**Lesson 9: Solving Problems Using an Organized List**

**Goal**

Use an organized list to solve number problems.

**Instructions for Use**

Disguise Combos asks you to determine how many disguise combinations there are for a number of wigs, beards, and glasses. By creating disguise combinations, you create organized lists.

Click on “Let’s Go!” to begin. Look at the disguise pieces and think of a good way to determine all the possible combinations. Drag a wig and a beard from the top of the screen onto Matt’s head to create a disguise combination. Each different combination you create will appear in a circle at the right after the message “Combo!” is shown. Continue until you’ve created all of the combinations. Then, click “Let’s Go!” to find the disguise combinations for the next character.

Bobbie Bear has you find out how many different outfits can be made using a number of shirts and pants. By creating outfit combinations, you create organized lists.

Look at the pants and shirts and think of a good way to determine all the possible combinations. Click and drag a shirt and then a pair of pants onto the bear. As each different outfit is created, it will appear in the space below the bear, along with the number of outfits made. When complete, click “Customize” to change the number of shirts or pants and start a new problem. For an extra challenge, enter a guess of the total number of outfits you will create by clicking “Make a Guess.” Enter your guess, then click “OK.” You may also change your guess at a later time.