ADDING AND SUBTRACTING FRACTIONS

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ADDING AND SUBTRACTING FRACTIONS

• Parts of a Fraction
• Changing Improper Fractions into Mixed
  Numbers and Vice-Versa
• How to Add Fractions
• How to Add Mixed Numbers
• How to Subtract Fractions
• How to Subtract Mixed Numbers
• How to Borrow When Subtracting Fractions

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PARTS OF A FRACTION
The top number of a fraction is the
numerator. The bottom number of a fraction is
the denominator.
3 4
3
QUIZ
MIXED NUMBERS AND IMPROPER FRACTIONS
To change a mixed number into an improper
fraction get MADMultiply Add Put over
Denominator 4 ½ 4 x 2 8 8
1 9
9 2
To change an improper fraction into a mixed
number divide the numerator by the denominator
whatever is left over is the new numeratorkeep
the same denominator. For Example 11 4
11 divided 4 equals 2 there is 3 left over.
34
2
4
Quiz Changing Mixed Numbers and Improper
Fractions

• Change the following into Improper Fractions.
  REVIEW
• 3 ½
• 5 5/8
• 12 1/3
• 15 ¾
• Change the following into Mixed Numbers.
  REVIEW
• 40/13
• 100/9
• 4/3
• 4. 9/2

CHECK
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ANSWERS Changing Mixed Numbers and Improper
Fractions

• Change the following into Improper Fractions.
• 1. 3 ½ 7/2
• 5 5/8 45/8
• 12 1/3 37/3
• 15 ¾ 63/4
• Change the following into Mixed Numbers.
  
• 40/13 3 1/13
• 100/9 11 1/9
• 4/3 1 1/3
• 4. 9/2 4 ½

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ADDING FRACTIONS
When adding fractions you MUST have a common
denominator!
Find the smallest number that both 4and 5 will go
into. This number is 20. Then multiply both the
numerator and denominator to get to 20.
19 20
Once you have a common denominator, then add!
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QUIZ
ADDING MIXED NUMBERS
3 3

• ½
• 5 1/3

X X
6 5
3/6 2/6
2 2

11 5/6
Find the least common multiple of 3 and 2. This
number is 6.
You MUST have a common denominator to add
fractions!
Once you have the common denominator, add the
fractions, then add the whole numbers!
6th Grade HomePage
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QUIZ
SUBTRACTING FRACTIONS
5 6 2 3
5 6 4 6
Find the least common multiple for 3 and 6. (In
this case, 6) Then multiply!
1 6
This is your answer!
To subtract fractions you must have a common
denominator!
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Answers Adding Fractions

• 3 1/5 2. 2
  ½
• 4 ¼
  1 ¾
• 5 1/6 4.
  1/3
• 2 2/3
  1/4
• 
  1/2

CHECK
Review
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QUIZ Adding Fractions

• 3 1/5 2. 2
  ½
• 4 ¼
  1 ¾
• 7 9/20
  3 5/4 4 1/4
• 5 1/6 4.
  1/3
• 2 2/3
  1/4
• 7 5/6
  1/2
• 
  13/12 1 1/12

Review
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QUIZ
SUBTRACTING MIXED NUMBERS
2 2 1 1

• 2/4
• ¼

• ½
• ¼

X X

1. ¼

To subtract fractions you must have a common
denominator!
Find the least common multiple of 4 and 2. This
number is 4.
ANSWER!
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SUBTRACTING FRACTIONS WHILE BORROWING
4/4
2 2 1 1

• 6/4
• 2 3/4

4 2/4 2 3/4

• ½
• ¾

X X
FirstFind a common denominator.
2 3/4
You cannot subtract 3 from 2, so you MUST borrow!
ANSWER!
Find the least common multiple of 4 and 2. This
number is 4.
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Quiz SUBTRACTING FRACTIONS

• ½ 2.
  3 ¾
• - ¼
  - 1 ½
• 4 1/5 4. 5
  
• - 1 1/2
  - 3 ¾

CHECK
Review Subtracting
Review Subtracting While Borrowing
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ANSWERS SUBTRACTING FRACTIONS

• ½ 2.
  3 ¾
• - ¼
  - 1 ½
• ¼
  2 ¼
• 4 1/5 4. 5
  
• - 1 1/2
  - 3 ¾
• 2 7/10
  1 ¼

Review Subtracting
Review Subtracting While Borrowing