Transcript Lattice method

Multiplying with
Multi-digit problems
I can multiply multi-digit whole numbers.
I can use a lattice to solve multi-digit multiplication
problems.
Essential Questions
What are whole numbers? How do we
multiply multi-digit numbers?
What is a place holding zero? When should
you use a place holding zero?
What is estimation? How should you use it to
determine the reasonableness of your
answer?
What is estimation? Why should you use it to
determine the reasonableness of your
answer?
Review Time!
Please get out your slates in
10...9...8...
On your slate, please solve this
problem using the standard method.
(Remember Turtle Head Method )
34 x 23
Hopefully you said... 782
Another way to look
at it... this is a lattice.
You need to remember
to take your time! There
are a lot of steps, and it
can be confusing.
Tens
2
Ones
3
To check your work!
Tens
Ones
3
4
20 x 30
600
20 x 4
80
To check
your
work!
+
=
+
+
+
30 x 3
4x3
+
90
12 =
=
=
=
= 782
+
600 + 80 = 680
90 + 12 = 102
600 + 90 = 690
80 + 12 = 92
Let’s try another,
together using a lattice.
You need to remember
to take your time! There
are a lot of steps, and it
can be confusing.
Tens
2
Ones
9
To check your work!
Tens
Ones
7
1
20 x 70
1400
20 x 1
20
To check
your
work!
1400 + 20 =
1420
+
=
+
+
+
70 x 9
1x9
+
=
630
9
=
=
=
= 2059
+
630 + 9 = 639
1400 + 630 =
2030
20 + 9 = 29
Your turn! Then we will go
over it together.
You need to remember
to take your time! There
are a lot of steps, and it
can be confusing.
Tens
4
Ones
3
To check your work!
Tens
Ones
3
9
40 x 30
1200
40 x 9
360
To check
your
work!
1200 + 360 =
1560
+
=
+
+
+
30 x 3
9x3
+
90
27 =
=
=
=
= 1677
+
90 + 27 = 117
1200 + 90 =
1290
360 + 27 =
387
Each student needs 12
pencils. If there are 24
students in a class, how
many do we need in all?
Now that you are
pros... Let’s try a
word problem :)
You need to remember
to take your time! There
are a lot of steps, and it
can be confusing.
Tens
1
Ones
2
To check your work!
Tens
Ones
2
4
20 x 10
200
40 x 1
40
To check
your
work!
200 + 40 =
240
+
=
+
+
+
20 x 2
4x2
+
=
40
8
=
=
=
= 288
+
40 + 8 = 48
200 + 40 =
240
40 + 8 =
48
Closure
Please write on your slates how the
lattice is a helpful tool.