Decimals, Fractions, and Percents

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Decimals, Fractions, andPercents
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Definitions

• Decimal - Any number shown with a decimal point
  a number based upon tenths or hundredths. ( 0.2,
  0.375, 86.4 )
• Fraction - One or more of the equal parts of a
  whole a number usually expressed in the form
  a/b. ( 1/3, 2 5/8, 7/4 )
• Percent- The word percent comes from Latin and
  means for each hundred or per hundred. (
  70, 6.5, 4.09 )

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Converting Fractions to Decimals

• Divide the numerator by the denominator.
• Do this until you get a decimal that terminates
  or repeats.
• If it repeats, place a bar ( ) over the first
  number that repeats.
• Example 1 Convert 3/4 to a decimal
• 3/4 34 0.75 (terminating decimal)
• Example 2 Convert 2/3 to a decimal
• 2/3 23 0.66 (repeating decimal)

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Converting Fractions to Percent

• Change the fraction to a decimal
• Multiply the decimal by 100 (move two places to
  the right)
• Put a percent sign ().
• Example 1 Convert 1/2 to a percent
• 1/2 1 2 0.50 (terminated)
• 0.50100 50 50
• Example 2 Convert 1/3 to a percent
• 1/3 13 0.33 (repeating)
• 0.33100 33 33

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Converting Decimals to Fractions

• Place the number that follows the decimal point
  over the place that it is in ( tenths,
  hundredths, thousandths, etc.).
• Simplify as necessary.
• Example 1 Convert 0.7 to a fraction
• 0.7 7/10 ( 7 is in the tenths place )
• Example 2 Convert 0.25 to a fraction
• 0.25 25/100 1/4 (25 is in the hundredths place.
  the GCF of 25 and 100 is 4 therefore 1/4 is the
  simplest form of 25/100)
• Example 3 Convert 1.625 to a fraction
• 1.625 1 625/1000 1 5/8 ( 625 is in the
  thousandths place. 5/8 is the simplified form of
  625/1000)

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Converting Decimals to Percent

• 1. Multiply the decimal by 100 and write the
  percent sign (), or move the decimal point two
  places to the right and write the percent sign
  ().
• Example 1 Convert 0.20 to a percent
• 0.20100 20 20
• Example 2 Convert 4 to a percent
• 4100 400 400

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Converting Percent to Fractions

• Change the percent to a decimal ( the by 100
  or move the decimal point 2 places to the left)
• Put the numbers behind the decimal point over the
  place that it is in ( tenths, hundredths,
  thousandths, etc.).
• Simplify as necessary
• Example 1 Convert 85 to a fraction
• 85 85 100 0.85 85/100 17/20 ( 85 is in
  the hundredths place. 17/20 is the simplified
  form of 85/100 )
• Example 2 Convert 12.5 to a fraction
• 12.5 12.5 100 0.125 125/10001/8 ( 125 is in
  the thousandths place. 1/8 is the simplified form
  of 125/1000 )

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Converting Percent to Decimals

• Divide the percent by 100 or move the decimal
  point 2 places to the left
• Example 1 Convert 72 to a decimal
• 72 72 100 0.72
• Example 2 Convert 62.5 to a decimal
• 62.5 62.5 100 0.625