Skill 6H
Subtraction: Use Addition to Check
Adding to check is a technique used to make sure the answer to a subtraction problem is correct.
Here, when telling your student to "add to check," he/she should know to make an addition problem by taking the answer to the subtraction problem and adding it to a number in the subtraction problem.  For example, using the subtraction problem 8 - 2 = 6, we would then "add to check" using 6 + 2 = 8.

Answer the subtraction problem,
then "add to check" to make sure the answer is correct.

subtract add to check

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