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COMPENSATION STRATEGY

Add too much on purpose, then subtract the extra. A slick mental shortcut.

L3L4
CS.N.3.2(III)
Section 1 / 3
THE OVER-ADD TRICK

Compensation means deliberately adding more than you need, then fixing it. To add 99, just add 100 and subtract 1. It sounds sneaky, but it is mathematically perfect!

99 + 47
1100 + 47 = 147
2Subtract 1 (you added extra): 147 − 1 = 146
= 146

LEADER TIP

Show both ways: add too much then subtract, or redistribute from one number to the other. Let students pick their favourite.

BEFORE THIS LESSON, TRY

🤝Friendly Numbers

PRACTICE WITH THESE GAMES

🔢Quick CalculateMath Sprint🎯Addition Quiz

Want more practice? Generate printable worksheets with similar problems.

Go to Worksheets

CONTINUE WITH:

🧠Mental Addition

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