Multipling Fractions

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Multipling Fractions
We have added and subtracted fractions. In this
lesson we will multiply fractions. When we add
and subtract fractions, we count how many of the
same size parts there are. When we multiply
fractions, the sizes of the parts change.
Consider this multiplication problem How much
is one half of one half?
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How much is one-half of one-half? Using a
fraction manipulative, we show one-half of a
circle.
To find one- half of one- half, we divide the
half in half.
We see this equals one- fourth.
Written out the Problem looks like this
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What fraction is one half of three fourths? Using
a fraction manipulative, we show three fourths of
a circle.
EXAMPLE 1
To find one half of three fourths, we divide each
fourth in half.
Since one half of one fourth is one eighth, one
half of three fourths is three eighths. We may
also find one half of three fourths by
multiplying.
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EXAMPLE 2
Multiply
We find two thirds of four fifths by multiplying.
Now Youre Cooking!
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Now that you know how to multiply fractions,
lets try some together.
2/3 x 2/3
3/5 x 1/2
1/3 x 2/3
4/9
2/9
3/10
3/4 x 1/2
1/2 x 1/3
1/2 x 1/4
1/2 x 2/2
3/8
1/8
1/6
2/4