Yolanda is finding 23,567-12,458. She added 2 to 12,458 before subtracting. Then she added it in again after she subtracted. Is her method correct? Explain.

This is what the problem is saying:

IS 23,567 - (12,458+2) + 2 equivalent to 23,567-12,458

If we check the first part, we get

23,567 - (12,458+2) + 2

=23,567 - (12,460) + 2

=11109

However, if we try the straightforward subtraction

23,567-12,458

=11109

This shows that her method is correct, even though it is a bit long.

In addition to this, if you've learned it, distributive property shows that we can change 23,567 - (12,458+2) + 2 into 23,567 - 12,458 - 2 + 2. Then, we can easily cancel out the - 2 and + 2 to get the regular subtraction expression 23,567-12,458