Introduction to Fractions

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Section 4.1

• Introduction to Fractions

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Identifying FractionComponents

• Numerator - The value above the fraction bar.
• Denominator - The value below the fraction bar.
• Example

The numerator is 9 The denominator is 11
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• Other Examples

• Recall that
• The fraction bar means divide.
• We cant divide by zero so the denominator cannot
  be zero.

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Writing Fractions to Represent Shaded Areas of
Figures

• Write a fraction for each shaded area
  shown below.

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• Draw and shade a part of a figure to represent
  each of the following fractions.

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Writing Fractions from Real-Life Data

• Of the nine planets, seven are farther from the
  sun than Venus is. What fraction of the planets
  are farther from the sun than Venus is?
• Six out of seventeen of a schools course
  offerings are electives. Find the fraction of the
  schools course offerings that are non-electives.

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Graphing Fractions on the Number Line

• Step 1 Divide up the distance from 0 to 1 into
  equal parts with the number of equal parts the
  same as the denominator value.
• Step 2 Start at 0 and count to the right the
  number of parts in the numerator value.
• Step 3 Put a dot ON the number line at this
  place.
• Note If the numerator is larger than the
  denominator, divide up the distance between
  subsequent integers as in step 1.

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Graph each fraction on a number line
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Simplifying Fractions of the Form a/a, a/1, and
0/a

• a/a 1 as long as a ? 0
• a/1 a
• 0/a 0 as long as a ? 0
• a/0 undefined (because we cant divide by zero)

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• Writing Equivalent Fractions
• To write equivalent fractions, we can
• Multiply the numerator and denominator by the
  same value.
• Divide the numerator and the denominator by the
  same value.
• Examples

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Now try these!

• Write

as an equivalent fraction with a denominator of
12.
Write
as a fraction with a denominator of 44.