BEATCALC:  Beat the Calculator!

___________________________________________
Back to Calculation Tips & Tricks
___________________________________________

From the BEATCALC mailing list:
a weekly service from B. Lee Clay, archived here by the Math Forum.
To subscribe to the BEATCALC mailing list, write to BEATCALC@aol.com.


   Squaring special numbers (3's and final 6)

  1. Choose a number with repeating 3's and a final 6.
  2. The square is made up of:
    • the same number of 1's as there are repeating 3's in the number;
    • one 2
    • one fewer 8 than there are repeating 3's;
    • a final 96.

   Example:

  1. If the number to be squared is 3336:
  2. The square has:

    three 1's (same as
       repeating 3's)     1 1 1
    one 2                       2
    two 8's (one fewer than
       repeating 3's)             8 8
    a final 96                        9 6

  3. So the square of 3336 is 11,128,896.

   See the pattern?

  1. If the number to be squared is 333336:
  2. The square has:

    five 1's (same as
       repeating 3's)   1 1 1 1 1
    one 2                         2
    four 8's (one fewer than
       repeating 3's)               8 8 8 8
    a final 96                              9 6

  3. So So 333336 x 3333336 = 111,112,888,896.


webmaster@forum.swarthmore.edu
15 September 1997
Web page design by Sarah Seastone