## Nines are awesome

Posted: July 27, 2013 in Blogging, Entertainment, Fun, General, Hobbies, Life, Tech, Tech and Life
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Interesting observation when you look at the angle increments on a circle, equally divided down to the smallest integer intervals (45° apart):

0°, (Twelve o clock), 45° (1.30), 90° (3.00), 135°, 180°, 225°, 270°, 315° and 360° – all the digits of these divisions add up to exactly 9.

And when you multiply 9 by anything, the digits of the answer also add up to 9, (except multiples of 11 x 9, which have to be divided twice, as in:  11 x 9 = 99 -> 9+9 = 18 -> 1 + 8 = 9).  or 22 x 9 = 189, 1 + 8 + 9 = 18, 1 + 8 = 9).

I plugged some randomly high numbers into a calculator to test the theory beyond what I can do in my head, and here’s what I got:

9 x 103 = 1107. 1 + 1 + 0 + 7 = 9.

9 x 358 = 3222.  3 + 2 + 2 + 2 = 9.

9 x 774456 = 6970104.  6+9+7+0+1+0+4 = 27.  2+7 = 9.

9 x 1155 = 10395.  1 + 0 + 3 + 9 + 5 = 18.  1 + 8 = 9.  Incidentally, 1155 is 105 x 11: another multiplication of 11.

Going in the other direction, 9 is 3 squared.  In binary, 3 is written as 11.

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