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Dividing Fractions Word Problem

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    A baby's T-shirt requires 4/5
    yards of fabric, or 4/5 of a
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    yard of fabric.
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    How many T-shirts can be
    made from 48 yards?
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    So what we want to do is we
    essentially want to say how
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    many groups of 4/5 of a yard
    can we make with 48 yards?
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    So you literally view this as
    we want to take 48 yards and
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    divide it into groups of 4/5
    of a yard, and say how many
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    groups are there?
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    Because each of those
    groups can make
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    one to baby's T-shirt.
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    If you give me 4/5 of a yard,
    one baby's T-shirt, so the
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    number of groups of 4/5 is the
    number of babies' T-shirts.
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    Now, when we divide by a
    fraction, we just have to
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    remember that that is the same
    thing, that is completely
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    equivalent to multiplying
    times the
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    reciprocal of the fraction.
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    So if we have 4/5 here,
    that'll be 5/4, the
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    reciprocal.
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    Now, you still might say, hey, I
    have a whole number here and
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    a fraction, and you just have
    to remember any whole number
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    can be written as a fraction.
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    This is the same thing
    as 48/1 times 5/4.
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    Now, we could just multiply it
    out at this point and figure
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    out what 48 times 5 is and
    that'll be over 4, but that'll
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    get big numbers and it'll be
    hard to kind of divide and all
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    that, but we could divide at
    this stage right here.
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    We could divide the numerator
    and the denominator by 4.
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    Or we could say, look, this is
    going to be equal to 48 times
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    5, whatever that is, over 4.
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    Now, let's divide the
    numerator by 4.
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    Well, we could divide 48 by 4,
    and we will get to 12, and
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    whatever we did to the
    numerator, we have to do to
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    the denominator, so if we
    divide 4 by 4, we get 1.
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    So then we're left with 12 times
    5, which is equal to 60.
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    12 times 5, which is equal to
    60/1, which is the exact same
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    thing as 60.
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    So you can actually make 60
    children's or babies' T-shirts
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    from 48 yards if each of
    them use 4/5 of a yard.
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Title:
Dividing Fractions Word Problem
Description:

U02_L2_T3_we5 Dividing Fractions Word Problem

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Video Language:
English
Duration:
02:08