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Multiplication and Division 21_Overview of Learning Plan
(Year 5) ACMNA098, NSW MA3-4NA
Equivalent division calculations result if both numbers are divided by a common factor.
Resources: playing cards, pencils, paper
Children:
Simplify
 divide numbers by a common factor to simplify a division
division by
calculation, for example,
dividing each
148 ÷ 8 =
number by a
74 ÷ 4 =
common
37 ÷ 2 =
factor.
1
18 2
Simplify
multiplication
by multiply
and dividing
by the same
number.
Children
 ask one another questions about simplifying division and
multiplication, for example:
 divide and multiply numbers by the same number to simplify a
multiplication calculation, for example,
6x4=
3x8
6x4=
12 x 2
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
How could we divide 148 by 8?

Do 148 and 8 have any common factors?

Is 2 a common factor of 148 and 8?

Could we divide both number by 2 to simplify the
calculation?

Could we divide 74 and 4 by 2 to continue to simplify
the calculation?

What is 37 divided by 2?

How could we simplify 6 times 4?

Could we double 4 and halve 6?

Is 6 times 4 equal to 3 times 8?

Could we double 6 and halve 4?

Is 6 times 4 equal to 12 times 2?
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Multiplication and Division 21_Explicit Learning Plan
(Year 5) ACMNA098, NSW MA3-4NA
Explain that equivalent division calculations result if both numbers are divided by a common factor.
Create and solve equivalent number sentences involving multiplication and division.
Resources: Playing cards, pencil, paper
EXPLICIT LEARNING
What could we do?
What language could we use to explain and ask questions?
Children think about, talk and listen to a friend about, then have the
Focuses
opportunity to share what they already know.
children’s
thoughts on the
concept, exposing
current
understanding and
any
misconceptions
►
Today brings an investigation about using common
factors to divide.
►
What do you know about using common factors to
divide?
►
Talk about using common factors to divide with a friend.
►
Is anyone ready to share what they are thinking about
using common factors to divide?

We’ve investigated factors.
Record, for example, factor: a number that can be multiplied to get
another number

And we found that a factor is a number that can be
multiplied to get another number.
Record, for example, 4 is a factor of 12

We found that 4 is a factor of 12 because if we multiply 4
by 3, we get 12.

So we also know that 3 is a factor of 12.

We’ve investigated common factors.
Reviews factors
Reviews common
factors
Record, for example, 4 x 3 = 12
Record, for example, 3 is a factor of 12
Record, for example, Highest Common Factors
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
And we found that a common factor is a factor of more
than one number.

We found that 1 and 3 are common factors of 12 and 15.

We’ve investigated highest common factors.

And we found that the highest common factor is the
highest number that is a factor of more than 1 number.

We found that 3 is the highest common factor of 12 and
15.

Today we’re going to investigate how we can make
division more efficient if we divide both numbers by a
common factor.

Let’s record a division number sentence, 148 divided by
8.

We could use the distributive property to divide 148 by
8.

But we already understand that!

Let’s look at our division number sentence.

Could we divide both numbers by a common factor?
Let’s investigate!

So let’s find a common factor of 148 and 8.

Both 148 and 8 are even numbers.
Record, for example,
Factors of 12 = 1, 12, 2, 6, 3, 4
Reviews highest
common factors
Factors of 15 = 1, 15, 3, 5
Common factors of 12 and 15: 1, 3
Introduces making Record, for example, highest common factor of 12 and 15 = 3
division more
efficient by
dividing both
numbers by a
common factor
(top)
Display a division number sentence, for example, 148 ÷ 8 =
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Divide both numbers by 2, for example, 148 ÷ 8 = 74 ÷ 4 =
Divide both numbers by 2, for example, 148 ÷ 8 = 74 ÷ 4 = 37 ÷ 2 =
1
Record, for example, 148 ÷ 8 = 74 ÷ 4 = 37 ÷ 2 = 18 2
Allow children time now to engage in guided and independent investigation of
dividing numbers by the common factor 2 to create equivalent division number
sentences.
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Email: [email protected]
Twitter: @learn4teach

So 2 must be a common factor of 148 and 8.

Let’s divide both numbers by 2.

Have we created an equivalent number sentence?

Will 74 divided by 4 be equal to 148 divided by 8?

Let’s look at our equivalent division number sentence.

Could we divide both 74 and 4 by a common factor? Let’s
investigate!

So let’s find a common factor of 74 and 4.

Both 74 and 4 are even numbers.

So 2 must be a common factor of 74 and 4.

Let’s divide both numbers by 2.

Have we created another equivalent number sentence?

Will 37 divided by 2 be equal to 84 divided by 4 and 148
divided by 8?

What is 37 divided by 2?

Is 37 divided by 2, 18 and a half?

Did we divide 148 by 8, by dividing both numbers by
common factors?
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Reviews making
division more
efficient by
dividing both
numbers by a
common factor.
Display another division number sentence, for example, 114 ÷ 6 =
Record, for example,
Factors of 6 = 2, 3
Circle the factors of 6 that are also factors of 114, for example,
Factors of 6 = 2, 3
Display the division number sentence, for example, 114 ÷ 6 =
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Twitter: @learn4teach

Let’s record a division number sentence, 114 divided by
6.

We could use the distributive property to divide 114 by
6.

But we already understand that!

So let’s find the common factors of 114 and 6.

Let’s start with the lower number because it will have
fewer factors.

Besides 1 and 6, what are the factors of 6?

Now let’s check if any of the factors of 6 are also factors
of 114.

Is 2 a factor of 114?

Yes, 114 is an even number so 2 is a factor.

Is 3 a factor of 114?

114 is 90 plus 24 – so 3 must be a factor of 114

So both 2 and 3 are factors of 114 and 6.

Let’s look at our division number sentence.

Could we divide both numbers by a common factor?
Let’s investigate!

Dividing 114 by 3 is not really much easier than dividing
114 by 6.

So let’s divide 114 and 6 by 2.

What does 114 divided by 2 equal?
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Record, for example, 114 ÷ 6 = 57 ÷ 3 =
Record, for example, 114 ÷ 6 = 57 ÷ 3 = 19
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
Does 114 divided by 2 equal 57?

What does 6 divided by 2 equal?

Does 6 divided by 2 equal 3?

Have we created an equivalent number sentence?

Will 57 divided by 3 be equal to 114 divided by 6?

Now we could divide 57 by 3 using the distributive
property and preferred multiples.

Is 3 a factor of 57?

Is 57, 30 and 27?

Are 30 and 27 multiples of 3?

Is 57, 3 less than 60?

Is 60 a multiple of 3?

What is 57 divided by 3?

Is 57 divided by 10 plus 9?

Is 57 divided by 3, 20 minus 1?

Is 57 divided by 3, 19?
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Introduces making Display another division number sentence, for example, 354 ÷ 6 =
division more
efficient by
dividing both
numbers by a
common factor.

Let’s record a division number sentence, 354 divided by
6.

We could use the distributive property to divide 354 by
6.

But we already understand that!

So let’s find the common factors of 354 and 6.

Let’s start with the lower number because it will have
fewer factors.

Besides 1 and 6, what are the factors of 6?

Now let’s check if any of the factors of 6 are also factors
of 354.
Circle the factors of 6 that are also factors of 354, for example,

Is 2 a factor of 354?
Factors of 6 = 2, 3

Yes, 354 is an even number so 2 is a factor.

Is 3 a factor of 354?

354 is 300 plus 54 – so 3 must be a factor of 354

So both 2 and 3 are factors of 354 and 6.

Let’s look at our division number sentence.

Could we divide both numbers by a common factor?
Let’s investigate!

Let’s divide 354 and 6 by 3.

What does 354 divided by 3 equal?

Is 354 300 plus 30 plus 24?

Does 354 divided by 3 equal 100 plus 10 plus 8?
Record, for example,
Factors of 6 = 2, 3
Display the division number sentence, for example, 354 ÷ 6 =
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Record, for example, 354 ÷ 6 = 118 ÷ 2 =
Record, for example, 354 ÷ 6 = 118 ÷ 2 = 59

Does 354 divided by 3 equal 118

What does 6 divided by 3 equal?

Does 6 divided by 3 equal 2?

Have we created an equivalent number sentence?

Will 118 divided by 2 be equal to 354 divided by 6?

Now we could divide 118 by 2 by halving.

What is half of 118?

Is half of 118, 59?

Is 118 divided by 2, 59?

Is 354 divided by 6, 59?
Allow children time now to engage in guided and independent investigation of
dividing numbers by a common factor to create equivalent division number
sentences.
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Email: [email protected]
Twitter: @learn4teach
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Children think about, talk and listen to a friend about, then have the
Introduces
equivalent number opportunity to share what they already know.
sentences
involving division
using common
factors (top)
►
Today brings an investigation about using common
factors to create equivalent multiplication and division
number sentences.
►
What do you know about using common factors to
create equivalent multiplication and division number
sentences?
►
Talk about using common factors to create equivalent
multiplication and division number sentences with a
friend.
►
Is anyone ready to share what they are thinking about
using common factors to create equivalent multiplication
and division number sentences?

We’ve investigated factors.
Record, for example, factor: a number that can be multiplied to get
another number

And we found that a factor is a number that can be
multiplied to get another number.
Record, for example, 4 is a factor of 12

We found that 4 is a factor of 12 because if we multiply 4
by 3, we get 12.

So we also know that 3 is a factor of 12.

We’ve investigated common factors.

And we found that a common factor is a factor of more
than one number.

We found that 1 and 3 are common factors of 12 and 15.
Record, for example, 4 x 3 = 12
Record, for example, 3 is a factor of 12
Record, for example, Highest Common Factors
Record, for example,
Factors of 12 = 1, 12, 2, 6, 3, 4
Factors of 15 = 1, 15, 3, 5
Common factors of 12 and 15: 1, 3
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Record, for example, 354 ÷ 6 = 118 ÷ 2 = 59
Record, for example, 46 ÷ 8 =
Record, for example, 46 ÷ 8 = 23 ÷ 4
6
3
Record, for example, 46 ÷ 8 = 5 8 = 5 4
3
Record, for example, 23 ÷ 4 = 5 4
Allow children time now to engage in guided and independent investigation of
creating equivalent division number sentences by dividing both numbers by a
common factor.
Website: http://www.alearningplace.com.au
Email: [email protected]
Twitter: @learn4teach

We’ve investigated division by dividing both numbers by
a common factor.

We found that 354 divided by 6 is equivalent to 118
divided by 2 because we divided 354 and 6 by 3.

Today we’re going to investigate using common factors
to create equivalent division number sentences.

Let’s create a division number sentence, 46 divided by 8

On the other side of the equals sign, let’s create an
equivalent number sentence.

Do 46 and 8 have any common factors?

Is 2 a common factor of 46 and 8?

Let’s divide both numbers by the common factor, 2.

Have we created an equivalent number sentence?

Does 46 divided by 8 equal 23 divided by 4?

What does 46 divided by 8 equal?

Does 46 divided by 8 equal 5 and three-quarters?

What does 23 divided by 4 equal?

Does 23 divided by 4 equal 5 and three-quarters?

Which number sentence was easier to solve?

Was it easier to solve 23 divided by 4, than 46 divided by
8?

When we create equivalent number sentences by
dividing both numbers by a common factor, does it
create an easier number sentence?
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Record, for example, 46 ÷ 8 = 23 ÷ 4
Introduces
equivalent number
sentences
involving
multiplication
using the same
Record, for example, 6 x 4 =
factors
Record, for example, 6 x 4 = 3 x 8
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Email: [email protected]
Twitter: @learn4teach

We’ve investigated division by dividing both numbers by
a common factor.

We found that 46 divided by 8 is equivalent to 23 divided
by 4 because we divided 46 and 8 by 2.

Today we’re going to investigate using the same factor to
create equivalent multiplication number sentences.

Let’s create a multiplication number sentence, 6 times 4.

On the other side of the equals sign, let’s create an
equivalent number sentence.

If we halve one number and double the other number,
will we have an equivalent number sentence? Let’s
investigate!

What is half of 6?

Is half of 6, 3?

Have we created an equivalent number sentence?

Does 6 times 4 equal 3 times 8?

What does 6 times 4 equal?

Does 6 times 4 equal 24?

What does 3 times 8 equal?

Does 3 times 8 equal 24?

When we divided one number by 2 and multiplied the
other number by 2, did we create an equivalent number
sentence? Why? Let’s investigate!
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Record, for example, x 4 = half as much as x 8

When we multiply by 4, do we get a number that is 4
times greater?

When we multiply by 8, do we get a number that is 8
times greater?

So when we multiply by 4, will we have half as much as
when we multiply by 8?

And when we multiply by 8, will we have twice as much
as when we multiply by 4?

If we multiply 6 by 4, will we have half as much as 6
times 8?

Does 6 times 4 equal half of 6 times 8?

Is half of 6 times 8, 3 times 8?

If we multiply 3 times 8, will we have twice as much as 3
times 4?

Does 3 times 8 equal twice 3 times 4?

Is twice 3 times 4, 6 times 4?

Let’s create another multiplication number sentence, 46
times 8.

On the other side of the equals sign, let’s create an
equivalent number sentence.

If we double one number and halve the other number,
will we have an equivalent number sentence? Let’s
investigate!
Record, for example, x 8 = twice as much as x 4
Record, for example, 6 x 4 = half of 6 x 8
1
Record, for example, 6 x 4 = half of 6 x 8 = 2 of 6 x 8
1
Record, for example, 6 x 4 = half of 6 x 8 = 2 of 6 x 8 = 3 x 8
Record, for example, 3 x 8 = twice 3 x 4
Record, for example, 3 x 8 = twice 3 x 4 = 2 x 3 x 4
Record, for example, 3 x 8 = twice 3 x 4 = 2 x 3 x 4 = 6 x 4
Record, for example, 46 x 8 =
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Record, for example, 46 x 8 = 92 x 4
Record, for example, 46 x 8 = 40 x 8 + 6 x 8 = 320 x 48 = 368
Record, for example, 92 x 4 = 90 x 4 + 2 x 4 = 360 + 8 = 368

What is double 46?

Is double 46, 92?

What is half of 8?

Is half of 8, 4?

Have we created an equivalent number sentence?

Does 46 times 8 equal 92 times 4?

What does 46 times 8 equal?

Does 46 times 8 equal 368?

What does 92 times 4 equal?

Does 92 times 4 equal 368?

When we multiplied one number by 2 and divide the
other number by 2, did we create an equivalent number
sentence? Why? Let’s investigate!

When we multiply by 4, do we get a number that is 4
times greater?

When we multiply by 8, do we get a number that is 8
times greater?

So when we multiply by 4, will we have half as much as
when we multiply by 8?

And when we multiply by 8, will we have twice as much
as when we multiply by 4?
Record, for example, multiply by 4 makes a number 4 times greater
Record, for example, multiply by 8 makes a number 8 times greater
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
If we multiply 92 by 4, will we have half as much as 6
times 8?

Does 92 times 4 equal half of 92 times 8?
Record, for example, 92 x 4 = half of 92 x 8 = 2 of 92 x 8 = 46 x 8

Is half of 92 times 8, 46 times 8?
Record, for example, 46 x 8 = twice 46 x 4

If we multiply 46 times 8, will we have twice as much as
46 times 4?

Does 46 times 4 equal twice 46 times 8?

Is twice 46 times 8, 92 times 4?
Record, for example, 92 x 4 = half of 92 x 8
1
Record, for example, 92 x 4 = half of 92 x 8 = 2 of 92 x 8
1
Record, for example, 46 x 8 = twice 46 x 4 = 2 x 46 x 4
Record, for example, 46 x 8 = twice 46 x 4 = 2 x 46 x 4 = 92 x 4
Allow children time now to engage in guided and independent investigation of
creating equivalent multiplication number sentences by dividing one number and
multiplying the other number by the same factor.
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