Download 3.2

3.2
What’s a Fraction?
What does a fraction look like?
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Fraction bar
Top = numerator
Bottom = denominator
Proper fraction = numerator is smaller than
denominator
Improper fraction = numerator is larger than the
denominator
Special note:
– Numerators can equal 0
– Denominators cannot equal 0
Mixed numbers
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Improper fractions can be put into the form of a mixed
number
Procedure:
Use the fraction bar as a division bar
Numerator goes inside the box,
Denominator outside
Remainders are the numerator
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Reverse the process:
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– Whole number times the denominator plus the numerator = new
numerator
– Denominators stay the same
Try it
Write as mixed #
 26/3
 36/4
 Write as an improper fraction
 9&4/7
 2&3/16
3
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Reduce your fractions
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Same as putting your fraction in simplest form
Divide the numerator and denominator by the
GCF
Ex 12/15
GCF = 3
12 divided 3 = 4
15 divided by 3 = 5
Reduced fraction = 4/5
Do this with every answer you get!
Scale up
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Ex1: 3/8 = ?/40
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Ex2: 5/13 = ?/39
Which is bigger?
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How to tell if one fraction is bigger than another
A. See if the fractions have the same denominator
B. If not, scale them up to the LCM of the denominators
(find the common denominator)
C. Compare the numerators to see which is bigger
Ex1: 5/12 and 7/18
A. Denominators not the same
B. LCM of 12 & 18 = 36
– 5/12 = 15/36
– 7/18 = 14/36
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C. 15 is greater than 14 so
 5/12 > 7/18
Try a few
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Put in simplest form
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21/84
32/12
11t/22
5z/5
Scale up:
 5/9 = ?/81
 8 = ?/12
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Which is bigger?
 4/9 or 8/21
 17/24 or 7/9
Homework
1- 135 eoo
 evens: 2 – 134 eoe (every other even)
 Also 136, 138
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