Fractions Complete Gude

8/3/2019 Fractions Complete Gude

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During this topic you will learn to:

Understand the equivalence of fractions.Simplify a fraction.

Change proper fractions to improper fractions.

Change improper to proper fractions

Add and Subtract fractions

Multiply and Divide fractions



1

2

2

5

3

9

4

8

2

6

2

8

5

15

1

4

46

24

37

59

4

12

9

18

410

25

75

30

75

4998

8

16

3

12

14

35

19

76

25

70

33

99



Before we can look at adding fractions weneed to get some practice in finding

equivalent fractions.

So long as you multiply the top and thebottom of a fraction by the same number

you will not change its size (because all you

are doing is multiplying by 1!)

e.g.,2

5x

4

4=

8

20

This is just 1 whole

so2

5=

8

20



Match up the fraction on the left with itsequivalent on the right.

2

5

1

3

3

7

4

9

3

8

19

57

24

60

12

28

24

64

84

189



An improper fraction is one where thenumerator (top number) is bigger than the

denominator (bottom number).

This means that there must be more than

one whole one.

e.g. = 13

2

=

15

4

=



e.g. = 13

2

=

15

4

=

= 11

2

= 3

3

4

An improper fraction can also be

written as a mixed number. This meansa whole number and a fraction.





If you can find equivalent fractions then

simplifying fractions should not be a problem.

Give me some equivalent fractions for:

12

18



Which one do you think is the simplest and

why?

12

18



Simplifying a fraction just means finding an

equivalent fraction with the smallest numbers

possible

12

18





To convert an improper fraction into a mixed

number:

How many times does the denominator go

into the numerator ?

This is the whole number part.

The remainder is the numerator of the

fraction part.



Example:

How many times does 9 go into 38?

What is the remainder?

389

= 4 29



To convert a mixed number into an improper

fraction :

Multiply the whole number by the

denominator then add the numerator

This is the numerator of the improper

fraction

The denominator stays the same.



Example:

3 57

How many sevenths is 3 whole ones?

3 x 7 = 21

=217

+57

=267





What do you think the answer to this is:

1

2+

1

2=

2

4=

1

2

We know that 2 halves make a whole one:

1

2+

1

2=

2

2= 1

All we add are the numerators, the

denominator sta s the same.

We can’t just add numerators and denominators or

we end up saying 2 halves make a half





Before we can add fractions we have tomake sure the denominators are the same

This is where our equivalent fractions come

in: 2

3+

5

6

We have to turn the thirds into sixths

2

3+

5

6=

4

6+

5

6=

9

6





This is the easiest operation to do with

fractions.

Just multiply the numerators to get thenumerator of the answer,

And multiply the denominators to get the

denominator of the answer.

e.g. 2

5x

3

7=

6

35



You can treat division just like multiplication

– there is just one step to do first.

Turn the fraction you are dividing by upsidedown.

Then change the division to a multiplication.

e.g. 2

5

3

7=

2

5x

7

3=

14

15

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Fractions Complete Gude