Very interesting approach. For those who are interested in more "different" math, google (or wikipedia) for "vedic math" (from Sanskrit Véda, "knowledge"); an a

Very interesting approach. For those who are interested in more "different" math, google (or wikipedia) for "vedic math" (from Sanskrit Véda, "knowledge"); an ancient Indian system of mathematics a bit different from the typical western teachings, said to better adhere to how the human mind works. Some amazingly efficient techniques for arithmethics on both paper and in head are to be found there.