1
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2
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Find the reciprocal of 2 and 4/5.

3
00:00:03,960 --> 00:00:06,839
So if we want to invert this fraction, we have to write it

4
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as a pure fraction first, or as an improper fraction.

5
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Right now, it's just a mixed number.

6
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So let's just write it as an improper fraction.

7
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So 2 and 4/5, if we write it as an improper fraction, it's

8
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still going to be over 5, but the numerator is now going to

9
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be 5 times 2 plus 4, and that's because 2 is 10/5, or 2

10
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times 5 fifths.

11
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So let's write it like that.

12
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So it's going to be 2 times 5 plus 4.

13
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14
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2 times 5 is 10.

15
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10/5 is the same thing as 2, and then the 4/5 is this 4/5

16
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right there.

17
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So this is going to be equal to 2 times 5 is 10

18
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plus 4 is 14: 14/5.

19
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So these are equivalent fractions.

20
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This is written as a mixed number.

21
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This is written as an improper fraction.

22
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It's improper because the numerator is bigger than the

23
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denominator.

24
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Now we want to find the reciprocal.

25
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When you find the reciprocal, you just switch the numerator

26
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and the denominator.

27
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You just flip the fraction.

28
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So if you want to take the reciprocal-- let me do this in

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a new color.

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If we want to take the reciprocal of this, we just

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swap the 5 and the 14.

32
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So this is going to be-- instead of 14/5,

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it's going to be 5/14.

34
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And we're done!

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