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0-2 Fractions

Concepts & Objectives

Fraction Operations (Obj. 2)Perform operations on fractionswithout a calculator

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fraction An expression that represents the

quotient of two quantities

represents 2 out of3 or2 divided by 3

23

numerator

denominator

23

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equivalent

fractions

Fractions that look different but represent

the same number:

To reduce a fraction, divide the top andbottom numbers by a common factor:

To reduce fractions on the calculator:

=2 14 2

2 2 2 1

8 8 2 4

= =

6 6 3 2

15 15 3 5

= =

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Multiplying fractions is much easier than

adding or subtracting, so we will startwith that first.

You do not have to find a commondenominator to multiply or divide.

Steps for MULTIPLYING Fractions:

1. Multiply the numerators and the

denominators.

2. Simplify answer.

4 3

7 6

12

42

6

6

2

7

4 3

7 6

=

12

42=

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Steps for DIVIDING Fractions

1. Flip the second fraction

2. Multiply

3. Simplify answer. (Do not try to reducea division problem until after you haveflipped the second fraction!)

3 2

4 3

3 3

4 2

=

9

8

3 3 9

4 2 8

=

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ADDING/SUBTRACTING Fractions

1. Find the LeastCommon Denominator

*a multiple of both denominators

(6 is the LCM of 2 and 3)

2. Make an equivalentfraction with the newdenominator.

3. Add numeratorsONLY and keep thedenominator.

4. Simplify if necessary.

5

6

1

2

3

3

5

63

6

5

63

6

2

6

53=2

2

6

2

2

1

3

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Practice1 3

1.2 5

=i4 2

2.5 5

=i

1 23.

4 3

=

3 44.

5 3=i

3 15.5 7 =

1 16.4 2 =

1 57.

4 4

+ =7 2

8.

9 9

=

1 19. + =

3 4

1 310.

2 5+ =

3

10

8

25

2 1

12 6=

12 4

15 5=

3 7 215 1 5=

i 1 2 2 14 1 4 2= =

i

6 3

4 2

=5

94 3 7

12 12 12+ =

5 6 11

10 10 10+ =

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Practice4

11. 35

=i

112. 10

2 =

313. 5

4+ =

3 314. 1 24 5+ =

3 4 12

1 5 5=i

10 2 2020

1 1 1= =i

3 20 23

4 4 4+ =

7 13 35 52 87 4 5 20 20 20+ = + =

or3

54

or3 3 15 12 27 7

1 2 3 3 44 5 20 20 20 20

+ + + = + + = + =

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Fraction Operations RoundTable

Number yourselves from 1 to 4 startingwith the earliest birthday.

For each pair of fractions on yourworksheet, person #1 will find theproduct, #2, will find the quotient, #3will find the sum, and #4 will find thedifference.

When you receive the paper, check thework of the person who gave it to you. Ifyou believe the work is correct, initial itand praise that person; otherwise,

discuss it with him and arrive at ananswer you agree upon.

When you have finished all of the pairs,

raise your hands.