Transcript module1-11

MODULE 1
Lesson 11 – Model Division as the
unknown factor in multiplication
using arrays and tape diagrams.
Let’s skip count by 3s to solve.
5X3=
4x3=
15
12
MULTIPLY BY 3 PRACTICE SHEET
Lesson 11 Pattern Sheet 3 1
A STORY OF UNITS
Multiply.
multiply by 3 (1–5)
Lesson 11:
© 2014 Common Core, Inc. All rights reserved. commoncore.org
Model division as the unknown factor in multiplication using arrays
and tape diagrams.
19
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 x2=8
8÷2=4
CONCEPT DEVELOPMENT: RELATE ARRAYS TO TAPE DIAGRAMS, MODELING
DIVISION WHERE THE QUOTIENT REPRESENTS THE NUMBER OF GROUPS.
Rosie puts 2 lemon slices
in each cup of iced tea. She
usescan
a total
of the
8 slices.
We
count
number of
How
many to
cups
teahow
columns
findofout
does Rosie
make?
many
cups.
How might this array help us solve
8 ÷ 2 = _____
Reread the problem of the day and tell
someone near you what the unknown represents.
The columns in this
array show the
number of lemon
slices in one cup of
Rosie’s iced tea.
The unknown is the number
of cups used to make the ice
tea – or the number of
groups.
What is the total number of lemon 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)?
8 slices
= ? Cups
The number of groups
2 slices
= 1 cup
Watch how I show the number of slices in one cup.
Where do we see the cups in our diagram?
8 slices
= ? Cups
2 slices
IN THIS PROBLEM THE
UNKNOWN REPRESENTS THE
NUMBER OF GROUPS.
Talk to a partner about how the tape diagram helps you see the unknown in both equations.
8 slices = ? cups
8 ÷ 2 = _____
_____ x 2 = 8
MS. ALVES PUTS 21 PAPERS IN 7 PILES. HOW
MANY PAPERS ARE IN EACH PILE?
MS. ALVES PUTS 21 PAPERS IN 7 PILES. HOW
MANY PAPERS ARE IN EACH PILE?
MS. ALVES PUTS 21 PAPERS IN 7 PILES. HOW
MANY PAPERS ARE IN EACH PILE?
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?
How big are our groups?
The size of the groups
2 slices = 1 cup
array
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.
8 lemon slices
? cup
TAPE DIAGRAM