A missing addend is the unknown part in a whole-number addition relationship, such as ; the learner determines it by identifying the difference between the known addend and the total, using subtraction, counting on, or a part–part–whole model. This connects addition and subtraction as inverse operations and supports reasoning about place value and later unknowns in equations; the scope is whole-number situations with totals within 100, not fractions, negative numbers, or generalized algebraic equations.
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Detailed Explanation: Find a missing addend
A missing addend is the number that is needed to complete an addition problem.
Example:
Think: “What number can I add to to make ?”
Use subtraction to find the missing part:
So, the missing addend is .
Check your answer by adding:
Therefore,
The missing addend is . Subtraction helps because it finds the difference between the total and the known addend.
Learn by doing: Find a missing addend
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Practice:
Addition - Missing Value, 2 Digit, 2 Numbers
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This Worksheet Includes:
- Addition - Missing Value, 2 Digit, 2 Numbers
- Addition - Missing Value, 2 Digit, 1 Number
- Addition - Missing Value, Within 20
- Addition - Missing Value, Within 10
- Addition - Whole Number - Number Bonds to 5
- Addition - Missing Value, Multiples of Tens
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