3-11 Adding a Group

3-11 Adding a Group

Math Message

Suppose you are arranging chairs for a class show. On your whiteboard, draw 5 rows with 4 chairs in each row. Write a number model that shows the total number of chairs.

Helper Facts

• Helper facts are multiplication facts that you know that can help you figure out facts that you don't know.

• Helper facts may be 2s, 5s, and 10s.

• We are going to use helper facts in a strategy called, adding a group.

Math Journal Page 90

Complete #1

Math Journal page 91

Complete #2

Open Ended

How do you know whether a fact is a helper fact for you?