A missing addend is the unknown part in a whole-number addition equation, such as or ; it can be determined by interpreting the total and known addend as part–whole quantities and finding their difference. Understanding the inverse relationship between addition and subtraction supports efficient reasoning with multi-digit numbers, place value, and bar-model or equation representations, without extending here to fractional, decimal, or general algebraic unknowns.
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Detailed Explanation: Find missing addends
A missing addend is the number that completes the total. To find it, subtract the known addend from the total:
Example:
- The total is , and the known addend is .
- Subtract the known addend from the total:
- The missing addend is .
- Check by adding:
So,
Learn by doing: Find missing addends
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Practice:
Addition - Missing Value, 3 Digit, 1 Number
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Download/Modify Free Grade 4 'Find missing addends' Worksheet
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This Worksheet Includes:
- Addition - Missing Value, 3 Digit, 1 Number
- Place Value - Missing a Place
- Addition - Missing Value, Multiples of Hundreds
- Addition - Missing Value, 2 Digit, 1 Number
- Addition - Missing Value, Multiples of Tens
- Addition - Missing Value, Multiples of Thousands
- Addition - Missing Value, Within 20
- Addition - Missing Value, To Multiples of Thousands
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