Transcript MALT©2006 Maths/Fractions Slide Show

Fractions Lesson 3
Understanding equivalent
fractions
MALT©2006 Maths/Fractions Slide Show : Lesson 3
These numbers are called
1
2
fractions
3
15
5
6
2
3
12
22
4
7
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Here are some
mixed numbers
2
1
3
1
3
6
8
2
5
5
4
9
2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
1
4
Today’s lesson looks at
Equivalent
fractions
6
8
3
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
WALT : to understand equivalent
fractions and decide if fractions
are equal
6
8
3
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
In the word equivalent
there is the root word
equal
6
8
3
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Fractions which are said to be
equivalent are equal to each
other.
6
8
3
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
For example
2
4
1
2
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So if you were given 2 quarters of
a cake and your friend was given
half a cake would you both have
the same amount?
2
4
1
2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Yes!
These fractions are equal.
These are equivalent fractions.
2
4
1
2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Can you tell if the following
fractions are equal?
Are they equivalent fractions?
3
6
1
2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Yes these fractions are equal.
They are equivalent fractions.
3
6
1
2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Are they equivalent fractions?
4
6
2
3
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Yes they are
equivalent fractions.
4
6
2
3
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Are they equivalent fractions?
3
12
1
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Yes they are
equivalent fractions.
3
12
1
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Are they equivalent fractions?
2
5
1
3
MALT©2006 Maths/Fractions Slide Show : Lesson 3
No, they are not equal.
They are not equivalent fractions.
2
5
1
3
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Here are some equivalent
fractions.
Can you work out a strategy for
deciding whether they are equal?
2
8
1
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Here are some equivalent
fractions.
Can you work out a strategy for
deciding whether they are equal?
4
10
2
5
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Here are some equivalent
fractions.
Can you work out a strategy for
deciding whether they are equal?
3
9
1
3
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Use thinking time to discuss.
1
4
3
12
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Use thinking time to discuss.
5
10
1
2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What ideas have you come up
with?
5
10
1
2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Explain your
strategy to the class.
5
10
1
2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
There is a relationship between
the fractions using dividing and
multiplying.
5
20
1
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What ever you do to the
top number . . You must
do to the bottom number.
5
20
1
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What ever you do to the top number . .
You must do to the bottom number.
divide by 5
1
4
5
20
divide by 5
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What ever you do to the top number . .
You must do to the bottom number.
divide by 2
1
2
2
4
divide by 2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What ever you do to the top number . .
You must do to the bottom number.
divide by 3
1
4
3
12
divide by 3
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What ever you do to the top number . .
You must do to the bottom number.
divide by 4
1
5
4
20
divide by 4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What ever you do to the top number . .
You must do to the bottom number.
divide by 2
1
4
2
8
divide by 2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What ever you do to the top number . .
You must do to the bottom number.
multiply by 3
3
5
9
15
multiply by 3
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What ever you do to the top number . .
You must do to the bottom number.
multiply by 2
2
9
4
18
multiply by 2
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What is the missing number?
1
5
10
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What is the missing number?
4
8
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
What is the missing number?
32
40
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Well done
32
40
4
5
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Sometimes you might need to work out
equivalent fractions in
three steps.
48
64
6
8
3
4
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Follow up task
H7 Textbook
Page 38
Questions 1,2,3
MALT©2006 Maths/Fractions Slide Show : Lesson 3
Answers
MALT©2006 Maths/Fractions Slide Show : Lesson 3
End of this lesson,
any questions or
comments?
MALT©2006 Maths/Fractions Slide Show : Lesson 3