Fraction Multiplication

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Fraction Multiplication

• And Cancelation

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Fraction Multiplication

• Here are some fraction multiplication problems
• Can you tell how to multiply fraction from these
  examples?

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Recall that multiplication by a whole number can
be represented as repeated addition. For example,
4 5 5 5 5 5. You can multiply a whole
number by a fraction using the same method.



3



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Multiply numerators
3
__



4
Multiply denominators
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One way to find of is to make a
model. Find of .


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Multiplying Fractions

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Multiplication

• Multiply numerator by numerator
• And denominator by denominator

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Try some.

• Multiply the following

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Answers

• Multiply the following

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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, then
  multiply.

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Try some

• Change any whole or mixed numbers to improper.
• Multiply straight across.
• Simplify answers

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Answers

• Change any whole or mixed numbers to improper.
• Multiply straight across.
• Simplify answers

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Cancelling

• Reduce before you multiply

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Canceling

• Reducing before multiplying is called canceling.
• ICK! Instead think the following in your head.

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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.