How to Find Missing Addend
Concept
A missing addend is a missing term in an addition sentence that includes at least one other addend and the sum The process involves how to solve a problem using subtraction if only one addend and the sum are known.
Rules
Find the missing addend using counters.
1. Model the given sum on the tens frame.
2. Remove the number of counters indicated by the given addend.
3. Count the remaining number of counters. This value is the missing addend.
4. Check your answer by adding both addends. The answer should be the same as the sum.
Find the missing addend using number sentence.
1. Subtract the given addend from the sum to find the missing addend.
2. Check your answer by adding both addends. The answer should be equal to the sum.
Example
Find the missing number.
4 + ____ = 10
Solution
Find the missing addend using counters
1. Model the given sum on the tens frame.
2. Remove the number of counters indicated by the given addend.
3. Count the remaining number of counters. This value is the missing addend.
Missing addend is 6
4. Check your answer by adding both addends. The answer should be the same as the sum.
4 + 6 = 10
Find the missing addend using number sentence.
1. Subtract the given addend from the sum to find the missing addend.
10 – 4 = 6
2. Check your answer by adding both addends. The answer should be equal to the sum.
4 + 6 = 10
Practice How to Find Missing Addend
Practice Problem 1
Find the missing numbers.
Use the counters to help find the answer.
Practice Problem 2
Find the missing numbers.
Practice Problem 3
Find the missing numbers.
Addition – a mathematical operation in which two or more numbers are combined to equal a greater number.
Addend – a number which is added to another.
Sum – Final answer of the addition.
Subtraction – to take away from a group or a number of things.
Related Skills
Fact families
Add 2 digits and 1 or 2 digits number – without regrouping
Add a two-digit and a one-digit numbers with regrouping
Add 2 two-digit numbers with regrouping
Subtract 1 or 2 digits numbers from 2 digits numbers without regrouping
Subtract 2 digit numbers from 2 digit numbers – with regrouping
Subtract tens
Subtraction – check your answer