MODULE 1 Lesson 11 – Model Division as the unknown factor in multiplication using arrays and tape diagrams.

5 X 3 = 4 x 3 = Let’s skip count by 3s to solve

MULTIPLY BY 3 PRACTICE SHEET

MULTIPLY BY 3 PATTERN SHEET 2 minutes End

PROBLEM OF THE DAY Rosie puts 2 lemon slices in each cup of iced tea. She uses a total of 8 slices. How many cups of tea does Rosie make? 4 x 2 = 8 8 ÷ 2 = 4

CONCEPT DEVELOPMENT: RELATE ARRAYS TO TAPE DIAGRAMS, MODELING DIVISION WHERE THE QUOTIENT REPRESENTS THE NUMBER OF GROUPS. 8 ÷ 2 = _____ The columns in this array show the number of lemon slices in one cup of Rosie’s iced tea. Rosie puts 2 lemon slices in each cup of iced tea. She uses a total of 8 slices. How many cups of tea does Rosie make? Reread the problem of the day and tell someone near you what the unknown represents. Reread the problem of the day and tell someone near you what the unknown represents. The unknown is the number of cups used to make the ice tea – or the number of groups. How might this array help us solve We can count the number of columns to find out how many cups.

What is the total number of lemon slices? 8 slices The question asks how many cups of ice tea Rosie makes. Do the cups represent the number of groups? Or do the cups represent the number of lemon slices in each group (size of each group)? The question asks how many cups of ice tea Rosie makes. Do the cups represent the number of groups? Or do the cups represent the number of lemon slices in each group (size of each group)? The number of groups = ? Cups

8 slices = ? Cups Watch how I show the number of slices in one cup. Where do we see the cups in our diagram? 2 slices = 1 cup

IN THIS PROBLEM THE UNKNOWN REPRESENTS THE NUMBER OF GROUPS. 8 ÷ 2 = _____ _____ x 2 = 8 8 slices = ? cups 2 slices Talk to a partner about how the tape diagram helps you see the unknown in both equations.

MS. ALVES PUTS 21 PAPERS IN 7 PILES. HOW MANY PAPERS ARE IN EACH PILE?

7 x ______ = 21 and 21 ÷ 7 = ________ WHAT DOES THE QUOTIENT REPRESENT IN THIS PROBLEM? The size of the groups How big are our groups?

array 8 lemon slices ? cup 2 slices = 1 cup TAPE DIAGRAM The tape diagram is a lot like a labeled and boxed array. They both show 4 groups of 2, but the labels make the tape diagram easier to use. The tape diagram is a lot like a labeled and boxed array. They both show 4 groups of 2, but the labels make the tape diagram easier to use.