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Multiplicationof

FractionFor Namrita mam

By Mudit Saxena

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Multiplication of Fraction Here are some fraction

multiplication problems

Can you tell how tomultiply fraction fromthese examples?

4 1 4

5 7 35v !

6 4 24

5 10 50v !

21

10

7

5

3

2!v

3 5 15

4 12 48v !1 1 1

3 3 9v !

2 5 10

3 1 3

v !

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Multiplication Multiply numerator by numerator

And denominator by denominator

2 5 10

3 1 3v !

1 2 1 2

1 2 1 2

N N N N

D D D D

v

v !

v

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Try some. Multiply the following:

4 2

9 3v !

1 5

3 8v !

2 4

3 5v !

5 5

8 8v !

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Answers Multiply the following:

4 2 8

9 3 2v !

1 5 5

3 8 24v !

2 4 8

3 5 15v !

5 5 25

8 8 64v !

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Mixed Numbers Because of the order of operations,

Mixed numbers cannot be multiplied as is

Change mixed numbers to improper fractions, thenmultiply.

!v

8

51

5

23

17 135 8

v ! 17 13 2215 8 40

v !

221 40 5 with a remainder of 21

21540

z !

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Try some Change any whole or mixed numbers to

improper.

M

ultiply straight across. Simplify answers

21 7

5v !

18

5v !

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Answers Change any whole or mixed numbers to

improper.

M

ultiply straight across. Simplify answers

2 49 41 7 9

5 5 1 5 5v ! v ! !

1 1 8 8 38 1

5 5 1 5 5v ! v ! !

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u t p cat on o ract on y

Whole numbers

Considering the cake example

above, if you have a quarter ofthe cake and you multiply the

amount by three, then you get

three quarters as your answer.

We can write this numerically asfollows:

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C

ancellingReduce before you multiply

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Canceling Reducing before mutiplying is called

canceling.

ICK! Instead of that do the following:-

1120

300

35

12

32

25!v

25 12 25 12 5 5 4 3

32 35 32 35 8 4 7 5

v v v v

v ! !

v v v v

5 5 4 3 5 3 15

8 4 7 5 8 7 56

v v v v

! !

v v v v

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Canceling on paper Rules: One factor from

any numerator cancels

with like factor from thedenominator. 12

15

20

9

21

16vv

4

16 9

21 20v

15v

3

12

16 4

4

9

21 20v

15v

3

312

164

4

9

21 20v

15v

3

1

312

1

164

1

4

9

21v

1

20

15v

3

1

3

121

16 41

21 7

9v

3

4 120

15v

3

1

312

1

3

7!

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Try one Say --- goes into ____ this many times.

As you cross each number out and write what is

left after canceling above the number.

10

1

3

5v

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Answer Say --- goes into ____ this many times.

As you cross each number out and write what is

left after canceling above the number.

5

1

13 10

v

2

56

!

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Try one more Make whole and mixed numbers improper

Cancel if you can

Multiply Numerators and denominators straightacross.

Simplify

415

14

2

1421

10 vvv

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Answer Make whole and mixed numbers improper

Cancel if you can

Multiply Numerators and denominators straightacross.

Simplify

10 1 14

4 421 2 15

10 9 14 48

21 2 15 1

v v v

v v v !

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Thanks

for

watching