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**copyright©amberpasillas2010**

Add and Subtract Fractions copyright©amberpasillas2010

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**3 4 Parts of a Fraction = the number of parts**

Add and Subtract Fractions Parts of a Fraction 3 = the number of parts 4 = the total number of parts that equal a whole copyright©amberpasillas2010

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**3 4 Parts of a Fraction = numerator = denominator**

Add and Subtract Fractions Parts of a Fraction 3 = numerator 4 = denominator copyright©amberpasillas2010

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**Add and Subtract Fractions**

A Common Multiple is a number that is a multiple of two or more numbers. Some multiples of 3 & 6 6, 12, 18, 24, 30, 36, 42 copyright©amberpasillas2010

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**Add and Subtract Fractions**

The LCM is the smallest multiple that two numbers have in common. 5 = 5, 10, 15, 20, 25, 30 6 = 6, 12, 18, 24, 30, 36 copyright©amberpasillas2010

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**To Add or Subtract Fractions With Unlike Denominators**

Add and Subtract Fractions To Add or Subtract Fractions With Unlike Denominators List the multiples of each denominator to find the LCM. 1 5 = 5, 10, 15, 20, 25, 30 1 + 10 = 10, 20, 30, 40, 50 copyright©amberpasillas2010

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**To Add or Subtract Fractions With Unlike Denominators**

Add and Subtract Fractions To Add or Subtract Fractions With Unlike Denominators Compare your lists. Which multiples do 5 and 10 have in common? 1 5 = 5, 10, 15, 20, 25, 30 1 + 10 = 10, 20, 30, 40, 50 copyright©amberpasillas2010

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**To Add or Subtract Fractions With Unlike Denominators**

Add and Subtract Fractions To Add or Subtract Fractions With Unlike Denominators Use the lowest common multiple as the denominator. 1 5 = 5, 10, 15, 20, 25, 30 1 + 10 = 10, 20, 30, 40, 50 copyright©amberpasillas2010

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**To Add or Subtract Fractions With Unlike Denominators**

Add and Subtract Fractions To Add or Subtract Fractions With Unlike Denominators This number is also called the least common denominator. 1 5 = 5, 10, 15, 20, 25, 30 1 + 10 = 10, 20, 30, 40, 50 copyright©amberpasillas2010

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**Add and Subtract Fractions**

SHORTCUT: Check to see if the smaller denominator divides evenly into the larger denominator. If it does, use the larger denominator for your LCD or LCM. 1 5 will divide evenly into 10, so 10 is your denominator. 5 1 + 10 copyright©amberpasillas2010

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**1 5 10 1 + 10 10 Add and Subtract Fractions**

Rewrite the fractions using the least common denominator or least common multiple. 1 5 10 1 + 10 10 copyright©amberpasillas2010

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**Add and Subtract Fractions**

Find the equivalent fractions for 1/5 & 1/10 with 10 as the denominator. You know that 1/10 is equal to 1/10 so Put a 1 over the Denominator of 10. 1 5 10 1 1 + 10 10 copyright©amberpasillas2010

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**Add and Subtract Fractions**

Find the equivalent fractions for 1/5 & 1/10 with 10 as the denominator. To find the top number, ask yourself what do you multiply the 5 by to get 10. 1 5 10 1 1 + 10 10 copyright©amberpasillas2010

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**Add and Subtract Fractions**

Find the equivalent fractions for 1/5 & 1/10 with 10 as the denominator. 2 Since you are looking for the equivalent fraction you know the numerator must also be multiplied by 2. 1 x 2 = 5 10 x 2 1 1 + 10 10 copyright©amberpasillas2010

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**2 1 5 10 1 1 + 10 10 Now just add the numerators. x 2 = x 2**

Add and Subtract Fractions Now just add the numerators. Remember when adding fractions you never add the denominators. 2 1 x 2 = 5 10 x 2 1 1 + 10 10 3 10 copyright©amberpasillas2010

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**Add and Subtract Fractions**

Identity Property states that any number multiplied by one equals itself This is useful to know so you can find a common denominator for adding and subtracting fractions.

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**1 2 8 1 + 8 8 Use the short cut to find the Least Common Denominator**

Add and Subtract Fractions Use the short cut to find the Least Common Denominator (LCD). 1 2 8 1 + 8 8 copyright©amberpasillas2010

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**1 2 8 1 + 8 8 x 4 = x 1 = Now find the equivalent fractions for**

Add and Subtract Fractions Now find the equivalent fractions for 1/2 & 1/8. 1 2 8 x 4 = 1 + 8 x 1 = 8 Ask what do you multiply 2 by to get 8 and what do you multiply 8 by to get 8. copyright©amberpasillas2010

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**1 4 2 8 1 + 8 8 x 4 = x 4 = x 1 = Since you are writing equivalent**

Add and Subtract Fractions Since you are writing equivalent fractions, now multiply the numerator by the same number you did on the denominator. 1 4 x 4 = 2 8 x 4 = 1 + 8 x 1 = 8 copyright©amberpasillas2010

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**1 4 2 8 1 1 + 8 8 x 4 = x 4 = x 1 = x 1 = Since you are**

Add and Subtract Fractions Since you are writing equivalent fractions, now multiply the numerator by the same number you did on the denominator. 1 4 x 4 = 2 8 x 4 = 1 1 x 1 = + 8 x 1 = 8 copyright©amberpasillas2010

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**1 4 2 8 1 1 + 8 8 5 8 x 4 = x 4 = x 1 = x 1 = Now add numerators.**

Add and Subtract Fractions Now add numerators. The denominator stays the same. 1 4 x 4 = 2 8 x 4 = 1 1 x 1 = + 8 x 1 = 8 5 8 copyright©amberpasillas2010

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**2 5 15 1 + 3 15 Find the least least common multiple for 5**

Add and Subtract Fractions Find the least least common multiple for 5 and 3. Write it as your denominator 2 5 15 1 + 3 15 copyright©amberpasillas2010

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**2 5 15 1 + 3 15 x 3 = x 5 = Ask yourself what do you multiply the**

Add and Subtract Fractions Ask yourself what do you multiply the denominator by to get 15. 2 5 15 x 3 = 1 + 3 x 5 = 15 copyright©amberpasillas2010

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**2 6 5 15 1 + 3 15 x 3 = x 3 = x 5 = Multiply the numerator by the same**

Add and Subtract Fractions Multiply the numerator by the same number you did in the denominator 2 6 x 3 = 5 15 x 3 = 1 + 3 x 5 = 15 copyright©amberpasillas2010

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**2 6 5 15 1 5 + 3 15 x 3 = x 3 = x 5 = x 5 = Multiply the numerator**

Add and Subtract Fractions Multiply the numerator by the same number you did in the denominator. 2 6 x 3 = 5 15 x 3 = 1 5 x 5 = + 3 x 5 = 15 copyright©amberpasillas2010

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**Add and Subtract Fractions**

Add your numerators. The denominator stays the same. 2 6 x 3 = 5 15 x 3 = 1 5 x 5 = + 3 x 5 = 15 11 15 copyright©amberpasillas2010

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**Add and Subtract Fractions**

1 2 x 2 = 6 12 x 2 = 1 3 x 3 = + 4 x 3 = 12 5 12 copyright©amberpasillas2010

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**ALWAYS SIMPLIFY YOUR ANSWER IF YOUR ANSWER IS AN IMPROPER FRACTION!**

Add and Subtract Fractions ALWAYS SIMPLIFY YOUR ANSWER IF YOUR ANSWER IS AN IMPROPER FRACTION! 4 12 x 3 = 5 15 x 3 = 2 10 x 5 = + 3 x 5 = 15 22 15 copyright©amberpasillas2010

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**1 7 15 22 15) 22 15 15 7 Add and Subtract Fractions**

ALWAYS SIMPLIFY YOUR ANSWER IF YOUR ANSWER IS AN IMPROPER FRACTION! copyright©amberpasillas2010

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**Add and Subtract Fractions**

5 20 x 4 = 6 24 x 4 = 1 3 x 3 = - 8 x 3 = 24 17 24 copyright©amberpasillas2010

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**Add and Subtract Fractions**

2 6 x 3 = 3 9 x 3 = 1 1 x 1 = - 9 x 1 = 9 5 9 copyright©amberpasillas2010

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**Add and Subtract Fractions**

4 2 x 2 = 4 8 x 2 = 2 2 x 1 = + 8 x 1 = 8 6 3 = 8 4 copyright©amberpasillas2010

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**Add and Subtract Fractions**

12 4 x 3 = 15 5 x 3 = 10 2 x 5 = - 15 3 x 5 = 2 15 copyright©amberpasillas2010

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**REMEMBER: To Always Show Your Work and The Giant One!**

Add and Subtract Fractions REMEMBER: To Always Show Your Work and The Giant One! Take out your study guide!!! copyright©amberpasillas2010

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**1 Add Fractions 12 4 15 5 10 2 + 3 15 22 15 #11 x 3 = x 3 = x 5 =**

Find a common denominator. 15 5 x 3 = 10 2 2) Add the numerators. x 5 = + 3 x 5 = 15 3) Keep the common denominator the same. 22 7 1 15 15 4) Simplify or reduce. Change improper fractions to mixed #s. 15) 22 15 7

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**- Subtract Fractions 5 x 4 = 20 6 x 4 = 24 1 x 3 = 3 x 3 = 8 24 17 24**

#12 5 x 4 = 20 6 x 4 = 24 Always SHOW YOUR WORK! This includes the Giant One. 1 x 3 = 3 - x 3 = 8 24 17 Giant One 24

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