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# Fraction Multiplication

Fraction Multiplication. And Cancelation. Fraction Multiplication. Here are some fraction multiplication problems Can you tell how to multiply fraction from these examples?. 14. 14. 14. 14. 34. __. __. __. __. __.

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## Fraction Multiplication

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1. Fraction Multiplication And Cancelation

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

3. 14 14 14 14 34 __ __ __ __ __ 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 • = = + +

4. There is another way to multiply with fractions. Remember that a whole number can be written as an improper fraction with 1 in the denominator. So 3 = . 3 __ 1 3 3 • 1 1 __ ______ __ 1 1 • 4 4 Notice that when you multiply a proper fraction and a number greater than 1, the product is between the factors. Multiply numerators 3 __ • = = Multiply denominators 4

5. 1 1 __ __ 4 3 1 1 __ __ 4 3 1 1 1 __ __ __ 4 3 12 One way to find of is to make a model. Find of . = •

6. Multiplying Fractions

7. Multiplication • Multiply numerator by numerator • And denominator by denominator

8. Try some. • Multiply the following:

9. Answers • Multiply the following:

10. Mixed Numbers • Because of the order of operations, • Mixed numbers cannot be multiplied as is • Change mixed numbers to improper fractions, then multiply.

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

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

13. Cancelling Reduce before you multiply

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

15. Try one • Say “--- goes into ____ this many times.” • As you cross each number out and write what is left after canceling above the number.

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