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Published byShona Price Modified over 8 years ago
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Integer Rod Operations Adding, Subtracting, Multiplying, and Dividing
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Six Steps Required 1.Represent the fraction with the smallest and least number of rods possible 2.Race the denominators to a tie. This will ALWAYS take 3 rows – the new common denominator is at the bottom
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Six Steps Required - Continued 3.Represent the fraction using the “race” as a guide using the common denominator rod and the least number of rods possible for the numerator 4.Do the operation
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Six Steps Required - Continued 5.Simplify the representation – least number of rods possible 6.Interpret the representation in #5 as a fraction number answer
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Do the Operation: Addition Use one common denominator bar Place both numerators (in order, from left to right) directly above the common denominator Total of 2 rows
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Simplify the Representation: Addition Use one common denominator bar Represent all with the least number of rods possible Total of 2 rows
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Addition – Semi-Concrete A. B. C. D. E. F. A. B. C. D. E. F.
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Addition – Semi-Concrete A. B. C. D. E. F. A. B. C. D. E. F.
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Adding – Semi-Abstract
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Do the Operation: Subtraction Use one common denominator bar Place the minuend (the sum) directly above the common denominator Place the subtrahend (addend) directly above the minuend (the sum) Use dashed lines to indicate the difference (missing addend) next to the subtrahend Total of 3 rows
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Simplify the Representation: Subtraction Use one common denominator bar Place the difference (missing addend) directly above the common denominator bar Represent all with the least number of rods possible Total of 2 rows
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Subtraction – Semi-Concrete A. B. C. D. E. F. A. B. C. D. E. F.
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Subtraction – Semi-Concrete A. B. C. D. E. F. A. B. C. D. E. F.
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Subtraction – Semi-Abstract
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Race Representation: Multiplication Use one common denominator bar The numerator will represent the SECOND factor only Do NOT represent the first factor
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Do the Operation: Multiplication Use one common denominator bar Place the numerator of the second factor directly above the common denominator Look at the first factor in the problem Treat the numerator of the second factor as the denominator of the first factor Place a bar above it that represents the numerator for the first factor Total of 3 rows
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Simplify the Representation: Multiplication Use one original common denominator bar Place the top bar from the step above directly above the common denominator bar Represent all with the least number of rods possible Total of 2 rows
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Multiplication – Semi-Concrete A. B. C. D. E. F. A. B. C. D. E. F.
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Multiplication – Semi-Concrete A. B. C. D. E. F. A. B. C. D. E. F.
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Multiplication – Semi-Abstract
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Do the Operation: Division Use one common denominator bar Place the divisor (the factor) directly above the common denominator Place the dividend (the product) directly above the divisor (the factor) Total of 3 rows
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Simplify the Representation: Division Use the divisor (the factor) as the new common denominator Place the dividend (the product) directly above the divisor (the factor) Represent all with the least number of rods possible Total of 2 rows
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Division – Semi-Concrete A. B. C. D. E. F. A. B. C. D. E. F.
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Division – Semi-Concrete A. B. C. D. E. F. A. B. C. D. E. F.
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Division – Semi-Abstract
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Representing Fractions Using Bars How do we represent fractions using integer bars? Part to whole Whole changes as necessary to make equivalents A train is two rods put together – ALL trains must have at least one E in them We will ALWAYS use the least number of bars possible to make a representation Do NOT draw more lines on representations than necessary
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