How can a number line
help me solve 4 X 7 ?
I know how to
multiply…
But not
with a number
line!
In this lesson you will
learn how to multiply
by using an open number line.
Let’s Review
Multiplication Number Sentences
Times
Groups of
2 X 8 = 16
Factor
Factor
Product
Let’s Review
Open Number Lines
Open number
lines help us
3X
count up!
+3
0
3=9
+3
+3
9
Hops of
Core Lesson
Multiply 4 X 7
4 hops
of 7
Number of
hops…
The value of
each hop…
4 X 7 = 28
+7
0
+7
7
+7
+7
14
21
28
A Common Misunderstanding
Thinking the first factor has to be
the number of hops and the second factor has
to be the value of each hop.
The
commutative
7 hops
property
of 4lets us
switch factors
around.
4 X 7 = 28
++7 +
4
4
0
+
+7
4
+
4
+
+7
4
++7 +
4
4
28
The campers are going canoeing! There
are 8 canoes
and each canoe fits 3 campers.
How many campers can go canoeing?
Core Lesson
8 X 3 = 24
8 hops
of 24
3 campers
can go
canoeing!
+
3
0
+
3
3
+
3
6
+
3
9
+
3
12
+
3
15
+
3
18
+
3
21
24
In this lesson you have learned
how to multiply
by using an open number line.