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Multiplying two digit numbers

  1. May 7, 2006 #1
    I've been looking on this forum but I haven't been able to find it.
    There was once a post with a link that brought me to a site where it showed you how to easily multiply two digit numbers together,and as well as things like 123 x 78. Does anybody know of a site that does this?

    I think it was something like 'sixteen principles of mathematics' or of such.
  2. jcsd
  3. May 7, 2006 #2
  4. May 7, 2006 #3
    Thanks for the book,I just requested it from the public library.
  5. May 7, 2006 #4
    It an ok book, but its hard to kick the habbits of a lifetime when it comes to doing this kind of thing i find, wish i had noticed this kind of method 20 years ago :P
  6. May 8, 2006 #5
  7. May 8, 2006 #6
    Flake, that is EXACTLY the same site I had found before. Thanks a lot.
  8. May 8, 2006 #7
    Wow, Mental Calculation... I absolutely suck at it.. I have to write things down if I want to calculate it.....
  9. May 9, 2006 #8
    Yeah i am much less prone to errors when doing it in written form, its very dependant on how many digits you can manipulate at a time in short term memory i understand. It can be trained but is generally much better when done from an early age.

    Its actually funny that i can manipulate larger numbers faster if I imagine a white-board marker in my mind and perform the sum visually on the imaginary board.

    Other good techniques which ive heard help are imagining unique colours to variables, alot like C++ Keyword/syntax highlighting.

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