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1. 7.4 Dividing Fractions
Mr. Williams
GESD
jwilliams@gesd40.org
Objective: Use reciprocals to divide fractions in
class and on a worksheet.
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2. Vocabulary
5 3
Reciprocal ­ two numbers, whose product is one. (Such as and )
3 5
3
12
12
What is the reciprocal of ?
3
2

3. Warm Up ­ Answer these in your math notes.
1 1 1 5
2
+
8 4
x 6
1 2 3 1
+ 6 4 x 2
12
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4. Dividing Fractions is easy. It is just like multiplying fractions with one more step.
To divide a fraction, multiply by its reciprocal.
2 3 2 4
÷ = x
3 4 3 3 All you do is quot;switchquot; the
second fraction then multiply.
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5. Solve these problems in your math notes.
5 4 5 3
÷ = x
8 3 8 4
7 1 7 2
÷ = x
10 1
10 2
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6. Write a fraction divison problem in your math notes.
We will share some of them on the board.
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7. Dividing Fractions and Whole Numbers
1. Change the whole number into a fraction.
2. Find the reciprocal of your second fraction.
3. Multiply the fractions.
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8. So what does all that mean?
3
Divide 6 by
4
3 6 3 6 4
6 ÷ = = x
4 1 ÷ 4 1 3
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9. Solve these problems in your math notes.
9
10 ÷
3 =
2
12 ÷ 3 =
Finish this sentence:
You divide fractions by ...
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