Box 6–7 Three Methods for Muitidigit Addition

A Common U.S. Algorithm

  1. right to left

  2. add, carry to left

  3. add carry to top number, remember new number while adding it to bottom number

Accessible Generalizable Methods

  1. right to left

  2. carry goes below in answer space, keeping total together

  3. add 2 numbers you see, then increase that number by 1 for previous carry

  1. can be done in either direction

  2. add each kind of unit first, then add those totals

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