Real Life Fractions

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Real Life Fractions

• http//www.ed.gov/pubs/EarlyMath/8.jpg

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When do we use fractions?

• Cooking
• Measurement
• Telling time
• Money

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What is a fraction?

• Fractions show part of something. Such as pieces
  of a pizza, part of an hour, half a pound, a
  quarter of an dollar.
• The top of the fraction is the numerator. It
  tells the pieces.
• The bottom of the fraction is the denominator.
  It tells how many make up a whole.

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What the fraction looks like.

• Numerator 1 Part
• Denominator 2 Whole/All parts

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Equivalent Fractions

• Sometimes we can write a fraction more than one
  way. If we have 4 out of 6 slices of cake left
  we can write our fraction two ways, because 4/6
  2/3.
• 4/6 is shaded and also
• 2/3 is shaded.

http//www.mathleague.com/help/fractions/fractions
.htmwhatisafraction
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Equivalent Fractions

• Look to see if the numerator and denominator have
  a like factor. If they do, we can simplify the
  fraction. Examples 3 and 9 have like factors,
  so 3/9 1/3.

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Adding Fractions

• When we combine units the denominators need to
  bee the same. Meaning, when we add fractions, we
  have to have like denominators.
• 2 3 5 3 6
  9
• 7 7 7 11 11 11

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Common Denominators

• If you are not given like denominators, you have
  to find the least common denominator.
• Take your denominators, and factor them out.
• Then, match up any common denominators. Pull one
  factor for each match. For example 2x24 and
  2x36, so pull out one 2 since there is a 2 in
  each.

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Common Denominators

• Next, account for the numbers not matched up. So
  for 4 and 6, we would account for the 2 and 3
  that did not match up.
• We would multiply all the numbers together.
  Meaning the 2 and 3, with the number we took out
  earlier, which was a 2.
• So from 2 x 2 4 and 2 x 3 6, our denominator
  would be 2x2x312.

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Find the common denominator when given these two
fractions.

• 1 2 ?
• 3 9 ?
• Remember your denominators are 3 and 9.

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If you put 9 you are right!

• 3 x 1 3 and 3 x 3 9
• One 3 matches up, so take it out. The rest does
  not, so take the remaining 3 and 1 out.
• 3 x 3 x 1 9

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How to change into equivalent fractions.

• Once you have found your common denominator, you
  need to find the equivalent fractions.
• 1 3 Because we need 9 as our denominator,
• 3 9 we multiply 3 x 3 to get 9. What ever we
  multiply the denominator by, we do the same to
  the numerator.

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If our denominator has to be 12, try to find the
numerator.

• 3 ?
• 4 12

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If you said 9 you are correct!

• 3 9
• 4 12
• Because 4 x 3 12, you have to
• multiply the top by 3 also.
• 3 x 3 9

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Once you have like denominators you can add.

• Solve 3 2 ?
• 9 9 ?

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Exactly!

• 3 2 5
• 9 9 9
• Try this one next
• 2 1
• 3 5
• Remember you need to find like denominators.

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Did you get

• 2 1 13
• 3 5 15
• Why? Your denominator has to be 15, because 3
  and 5 have no like factors, so multiply 3 x 5
  15.
• 10 3 13
• 15 15 15

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Congratulations!

• You are on your way to mastering fractions.

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Works Cited

• Picture on Page 1
• http//www.ed.gov/pubs/EarlyMath/8.jpg
• Picture on Page 5
• http//www.mathleague.com/help/fractions/fractions
  .htmwhatisafraction
• All other pictures clip art.