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The common-core math standards require that students learn the standard algorithm for multi-digit adding and subtracting—you know, the process in which you line the numbers up vertically to add or ...

Addition and Subtraction Tricks Without Pen and Paper: Doing quick calculations without writing anything down can seem tricky, but with the right mental math techniques, students can easily learn to ...

A thorough understanding of addition and subtraction requires knowledge of the inverse relation between these operations. According to Piaget (1952), any inverse relation poses a significant challenge ...