INTRODUCTION TO FRACTIONS

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INTRODUCTION TOFRACTIONS
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FRACTIONS AS PART OF A WHOLE

• NUMERATOR
• DENOMINATOR

NUMERATOR How many you are talking about
DENOMINATOR How many equal parts the whole
(1) is divided into
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MIXED NUMBERS AND IMPROPER FRACTIONS

• MIXED NUMBER a whole number and a fraction
• Example 2 ½ 3 ¾
• IMPROPER FRACTION fraction with the numerator
  larger than the denominator
• Example

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To change from Improper Fraction to Mixed Number

• The fraction bar means divide.
• Divide the denominator into the numerator.
• Get the whole number.
• The remainder is the numerator of the fraction.
• EX

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To change from a Mixed Number to an Improper
Fraction

• Multiply the Whole Number times the Denominator
• Add the numerator
• This gives the new numerator.
• The denominator stays the same.
• You take the whole number times the bottom
  add the top
• EX 3 4/5 2 3/7

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• EQUIVALENT FRACTIONS
• Name the same number but look
• differently.
• Name the same
• Part of a whole
• Part of a set, or
• A location on a number line

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FINDING EQUIVALENT FRACTIONS

• Any number x 1 that number.
• Names for 1 as a fraction?
• 2/2, 3/3, 4/4, 5/5, 6/6, ...
• Whatever you do to the numerator (top), you
  must do to the denominator (bottom) to keep the
  value the same.

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FINDING EQUIVALENT FRACTIONS
Any number divided by 1 that number. Names for
1 as a fraction? 2/2, 3/3, 4/4, 5/5, 6/6,
... Whatever you do to the numerator (top),
you must do to the denominator (bottom) to keep
the value the same.
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• Look at the factors of the smaller number.
• Starting with its largest factor, check if it
  goes into the other .

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Divide by the biggest number that divides into
both the numerator and denominator.
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SIMPLEST FORM (SF) OR LOWEST TERMS (LT)

• DIVIDE by the GCF (Greatest Common Factor) of
  numerator and denominator
• (DIVIDE by the biggest number that goes into top
  and bottom)
• 1st try the numerator (top )
• If it does not work, think of the factors of the
  numerator (top )
• Try the factors starting with the biggest 1st

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SF OR LT EXAMPLES

• 1st try 8.
• Does 8 go into 16?
• Yes, so GCF is 8
• 8 divided by 8 1 16 divided by 8 2
• So

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SF OR LT EXAMPLES

• 1st try 14. Does 14 go into 21? NO
• Think of the factors of 14 1, 2, 7, 14
• 1st try 7. Does 7 go into 21? YES
• 14 divided by 72 21 divided by 73
• So

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SIMPLEST FORM (SF) OR LOWEST TERMS (LT)

• Never SF if there are 2 even numbersat least 2/2
  would work
• Have SF if GCF is 1
• Have SF if no number except 1 divides into
  numerator and denominator
• Ideally want to always divide by the GCF