Samples of mental computation
This page contains samples showing how students subtract mentally. Usually these problems would be done without any writing, but the movies and adult voice are used here to explain what has been done.
The samples demonstrate a great variety of methods including:
- complementary addition
- subtraction in stages
- rounding
- equal additions principle
- renaming principle
- other methods
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Ann
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Ben
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Sunil
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Loretta
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Fikeni
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Nina
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Jim
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Mary
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Tess
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Sam
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Peter
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Amy
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