Multiplying Fractions

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We're asked to multiply 5/6
times 2/3 and then simplify
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So let's just multiply
these two numbers.
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So we have 5/6 times 2/3.
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Now when you're multiplying
fractions, it's actually a
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pretty straightforward
process.
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The new numerator, or the
numerator of the product, is
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just the product of the two
numerators, or your new top
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number is a product of the
other two top numbers.
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So the numerator in our product
is just 5 times 2.
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So it's equal to 5 times 2 over
6 times 3, which is equal
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to-- 5 times 2 is 10 and
6 times 3 is 18, so
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it's equal to 10/18.
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And you could view this as
either 2/3 of 5/6 or 5/6 of
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2/3, depending on how you
want to think about it.
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And this is the right answer.
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It is 10/18, but when you look
at these two numbers, you
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immediately or you might
immediately see that they
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share some common factors.
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They're both divisible by 2,
so if we want it in lowest
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terms, we want to divide
them both by 2.
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So divide 10 by 2, divide 18 by
2, and you get 10 divided
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by 2 is 5, 18 divided
by 2 is 9.
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Now, you could have essentially
done this step
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earlier on.
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You could've done it actually
before we did the
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multiplication.
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You could've done
it over here.
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You could've said, well, I have
a 2 in the numerator and
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I have something divisible by 2
into the denominator, so let
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me divide the numerator by
2, and this becomes a 1.
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Let me divide the denominator
by 2, and this becomes a 3.
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And then you have 5 times 1
is 5, and 3 times 3 is 9.
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So it's really the same thing
we did right here.
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We just did it before we
actually took the product.
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You could actually
do it right here.
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So if you did it right over
here, you'd say, well, look, 6
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times 3 is eventually going
to be the denominator.
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5 times 2 is eventually going
to be the numerator.
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So let's divide the numerator by
2, so this will become a 1.
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Let's divide the denominator
by 2.
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This is divisible by 2,
so that'll become a 3.
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And it'll become 5 times 1
is 5 and 3 times 3 is 9.
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So either way you do
it, it'll work.
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If you do it this way, you get
to see the things factored out
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a little bit more, so it's
usually easier to recognize
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what's divisible by what, or you
could do it at the end and
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put things in lowest terms.
Title:
Multiplying Fractions
Description:

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Video Language:
English
Duration:
02:26
 dhbot edited English subtitles for Multiplying Fractions Martin B edited English subtitles for Multiplying Fractions Martin B edited English subtitles for Multiplying Fractions Martin B edited English subtitles for Multiplying Fractions Martin B edited English subtitles for Multiplying Fractions brettle edited English subtitles for Multiplying Fractions brettle edited English subtitles for Multiplying Fractions brettle edited English subtitles for Multiplying Fractions

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