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> That's what I learned in elementary school and have been using since then. It's interesting to know how others to do it.

well, i generally do it using a 'covolution approach' like this:

     45
   x 86
   ------
       0 (5*6 == 30) -> take the units place, and put '3' as carry over
      4  (6*4+8*5+3 == 47) -> take the units place, and put '4' as carry over
    36   (8*4+4 == 36)
-------------

   3640
-------------

with sufficient practice, you can multiply arbitrary 3 digits in approx 10-15 seconds or so ;)

[edit-1]: my formatting sucks, cannot seem to align stuff nicely at all.




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