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Reciprocal of a Mixed Number

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    Find the reciprocal of 2 and 4/5.
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    So if we want to invert this fraction,
    we have to write it
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    as a pure fraction first, or
    as an improper fraction.
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    Right now, it's just a mixed number.
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    So let's just write it as an improper fraction.
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    So 2 and 4/5, if we write it as
    an improper fraction,
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    it's still going to be over 5, but
    the numerator is now going to
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    be 5 times 2 plus 4, and that's
    because 2 is 10/5, or 2 times 5 fifths.
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    So let's write it like that.
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    So it's going to be 2 times 5 plus 4.
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    2 times 5 is 10.
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    10/5 is the same thing as 2, and
    then the 4/5 is this 4/5 right there.
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    So this is going to be equal
    to 2 times 5 is 10
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    plus 4 is 14: 14/5.
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    So these are equivalent fractions.
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    This is written as a mixed number.
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    This is written as an improper fraction.
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    It's improper because the
    numerator is bigger than the denominator.
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    Now we want to find the reciprocal.
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    When you find the reciprocal, you just
    switch the numerator and the denominator.
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    You just flip the fraction.
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    So if you want to take the reciprocal.
    Let me do this in 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.
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    So this is going to be: instead of 14/5,
    it's going to be 5/14.
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    And we're done!
Title:
Reciprocal of a Mixed Number
Description:

U02_L2_T3_we1 Reciprocal of a Mixed Number

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Video Language:
English
Duration:
01:41

English subtitles

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