Question

Maria has 39 books in her library she bought several books at a yard sale over the weekend she now has 70 books in her library how many books did she buy at the yard sale

Answer 1

This question could be answered by subtracting 70 - 39. 70 - 39 = 31. Therefore your answer will be 31

Answer 2

So 39 books and it must equal 70. So 39 + ___ = 70 or, to make it a bit simpler, 70 - 39 = ___. You should be able to do that.