Download Topic 6 - Lesson 1

Lesson 6-1
CCSS 4.NBT.5
How do I know which
computational
method (mental math,
estimation, paper and
pencil, and calculator) to
use?
How do mathematical
operations relate to
each other?
Why do I need
mathematical
operations?
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4X8
9X7
5X5
3X6
8X6
7X7
In this lesson, you will learn an
algorithm to help you record the partial
products as you multiply.
Let’s look at the Envision Video for this
lesson and take the quiz.
We use arrays to solve multiplication problems
by representing the problem as a number of
rows with equal objects in each row.
In real life what can you think of that comes in
rows?
 Array:
A strategy used to solve a multiplication
problem by drawing equal rows with an equal
number of objects in each row. (Enter this
definition in your Interactive Math Notebook)
 Example: For the problem 2 x 4, you would make 2
rows with 4 objects in each row.
 How can you make an array to show 4 X 12?
 Look at the tens and ones in the 12 as two different
numbers. Make an array for 4 X 1, and another for
4 X 2.
 Remember that since the 1 is in the tens place,
and 4 X 1 = 4, it is really worth 40. 4 X 2 = 8
 Now add 40 + 8.
Matt arranges his
video games in 4
rows with 16 games
in each row. Build
an array to show
Matt’s games.
Abby bakes 3 rows of
cupcakes with 14
cupcakes in a row.
Build an array to find
out how many
cupcakes Abby
baked.
Tyler puts his
baseball cards in 4
rows with 26 cards
per row. Build an
array to find how
many cards Tyler
has in all.
Gavin puts his
dinosaurs into 3 rows
with 22 dinosaurs in
each row. Build an array
to see how Gavin
arranged his dinosaurs
and find his total
number of dinosaurs.
Kara bakes cookies
in 6 rows with 16
cookies per row.
Build an array to
find out how many
cookies Kara baked
in all.
How many more stamps are in 4 rows of rocket
stamps than 5 rows of flower stamps?
Type of Stamps
Rocket
Presidents
Flower
Number Per Row
30
24
22
 In this lesson, you recorded multiplication after finding
partial products using an expanded algorithm.
 Reflection in Notebook: At the end of this unit, I want to
be able to...
 Center Activity – Toss and Talk (6-1).
 Homework (6-1 Practice) for one “Paw Signature” and
(6-1 Reaching & Practice) if you want two “Paw
Signatures.”
 Website for Practice: Website for Practice:
http://www.mathplayground.com/multiplication01.html