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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 ...

There's a whole world under the surface and only Ron has any idea about it. And sometimes the two worlds collide, and sometimes they don't. Ron holds them at arm's length from each other. Watch every ...