Missing Addend in Addition problems

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Use Addends in the Range

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Answers on a separate sheet

About this worksheet

Suits Years 1 to 3

The sums here have a hole in them: 4 plus something makes 9, what is the something? Your child fills in the missing number.

This flips addition into a puzzle and quietly teaches that adding and subtracting undo each other. It is also, truth be told, a first taste of algebra, years before anyone mentions the letter x.

How to make your worksheet

  1. Give the sheet a title, or keep the one suggested.
  2. Choose the range the numbers come from.
  3. Press Generate and print. Answers included.

Every press of Generate lays out a fresh sheet, ready to print on A4.

Common questions

How do children solve these?

Two good ways: count up from the 4 to the 9, or subtract 4 from 9. Both give 5. Children usually start with counting up, and discover subtraction hiding inside the puzzle later.

Why is this called early algebra?

Because 4 + _ = 9 is exactly 4 + x = 9 with a friendlier costume. The thinking, undo the addition to find the unknown, is the same thinking secondary school asks for.