• Labna@lemmy.world
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    9 hours ago

    9x7 = 70 - 7 = 63 in table of 9 too easy ! (nearly the same technic)
    8x7 = 70 - 7x2 = 70 - 14 = 6 + 70 - 20 = 56 (6 from 10-4 from 14)

    7x6 = 5x7 + 7 = 70/2 +7 = 35 + 7 = 42 the answer to the life, the death and all the rest (5xa = 10/2 x a= 10a/2)

    • pyre@lemmy.world
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      8 hours ago

      i mentioned the 5x trick elsewhere under this post but for me for some reason doing the halfing first is easier. so to me it’s a/2x10 instead.