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| − | == Fractions == | + | == Abacus/Worksheet == |
| − | ===The Fraction abacus===
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| − | Start Abacus [[File:Abacus-icon.png]],
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| | + | Read at https://help.sugarlabs.org/abacus_worksheet.html |
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| − | select the Fraction abacus.
| + | The source file has been moved to [https://github.com/godiard/help-activity/blob/master/source/abacus_worksheet.rst GitHub] |
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| − | [[File:Functionabacus.jpg]]
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| − | Slide one of the 1/2 beads to represent 1/2
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| − | [[File:Abacus1of2.jpg]] | |
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| − | Another way to represent 1/2 is to slide half of another string of fraction beads, for example slide 2 of the 1/4 beads. That is (2 x 1)/4 = 2/4 = 1/2
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| − | [[File:Abacus2of4.jpg]]
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| − | How many ways can you make 1/2, remember you can use 2 strings eg. 1/3 + 1/6 = 1/2
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| − | [[File:Abacus3p6.jpg]]
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| − | If using just one string, only some of the strings of beads can be used to make 1/2. Which ones? Why?
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| − | Show that the solutions which use more than one string are correct, use the Lowest Common Denominator ([http://en.wikipedia.org/wiki/Lowest_common_denominator LCD]) method, for example for the case of 1/3 +1/6 = 1/2
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| − | 1/3 + 1/6 =
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| − | 2/6 + 1/6 =
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| − | (2+1)/6 =
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| − | 3/6 =
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| − | 1/2
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| − | How do you know if you have found all the solutions?
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| − | Find all the ways to make 1/3 and 2/3
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| − | ===Other representations of fraction addition===
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| − | Draw your solutions as pie charts, you can use Paint, TurtleArt, Socialcalc or Gnumeric in Gnome.
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| − | [[File:1on2piedraw.jpg]] [[File:Fractionpieturtle.jpg]] [[File:Fractionpiesocialcalc.jpg]]
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| − | ===The Caacupé abacus===
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| − | Load the Caacupé abacus [[File:Abacuscaacupe.jpg]]
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| − | It can represent negative whole numbers and fractions. 1/2 can be represented as 10 - 9 - 2/3 + 1/6
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| − | [[File:Abacus10931.jpg]]
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| − | How many different ways can you represent 1/2 , 1/3, 2/3
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| − | How do you know when you have found them all?
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| − | Similar to the Pie chart, can you think of a way to visually represent the addition of positive and negative fractions?
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| − | see the [[Activities/Abacus/Worksheet/Answersheet | answersheet]]
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