A missing addend is the unknown part in an addition situation or equation, such as ; the learner determines it by relating the known part to the total, often counting on or finding the difference, with sums within 20. Part–whole diagrams, ten-frames, and number lines can represent this relationship and establish addition and subtraction as inverse operations, without extending to larger numbers or symbolic generalizations.
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Detailed Explanation: Find a missing addend
A missing addend is the number that makes the total.
Example:
- Start with the known number, .
- Count on until you reach :
- You counted numbers, so the missing addend is .
So, is the missing addend.
Learn by doing: Find a missing addend
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Practice:
Addition - Missing Value, Within 20
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This Worksheet Includes:
- Addition - Missing Value, Within 20
- Addition - Missing Value, Within 10
- Addition - Missing Value, To Ten
- Addition - Whole Number - Number Bonds to 5