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[[File:AddSub3 - Add-Renaming.png|300px|thumb|center|Regroup ObjectsAdd with Renaming]]  ====Add 3-Digit Numbers====  The teaching example illustrates two addition problems, each of which has two 3-digit numbers and requires renaming of either the ones or the tens. Each of the practice exercises which follow requires one renaming.  [[File:AddSub3 - 3DigitSub.png|300px|thumb|center|Add 3-Digit Numbers]]