Final answer:
The correct number sentence that completes the fact family is 12+6=18.
Step-by-step explanation:
The correct number sentence that completes the fact family is 12+6=18.
A fact family consists of a set of related number sentences using the same three numbers, where the two numbers are added together to get the third number. In this case, the fact family is 12, 2, and 6. So, the missing addition sentence would be 12+6=18.
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