Morris: Christmas = Halloween?!?

For me the holidays end on Monday so I just have time to post this seasonal question.

Why is Christmas the same as Halloween?

Specifically why is Oct. 31 = Dec. 25.

Hint: you need to look at exactly how this is written.


A short problem with a long pedigree.

I found this in Martin Gardner’s book ‘The Colossal Book of Short Puzzles and Problems’, problem 3.9 in my copy.  He credits Solomon Wolf Golomb, the inventor of Polyominoes which inspired tetris.

Isaac Asimov based a whole story on this puzzle,  ‘A Curious Case of Income Tax Fraud’, part of his Black Widowers series.


I asked some work colleagues and had some amusing answers, none of which were maths related.  Maybe you have your own?





  1. foley said,

    January 4, 2009 at 4:17 pm

    31 OCTal is 25 DECimal, unfortunately we don’t have a month name that starts with HEX with a holiday on the 19th, that’s a shame, I could certainly use another month each year.  On another matter,  I have declared today “Square Day” 1/4/9 and tried to post such to AIM, Myspace, Facebook, and Twitter at 16:25:36 Eastern time, but I was distracted at the last minute.

  2. Atreus said,

    January 6, 2009 at 7:37 pm


    Halloween OCTal 31= Christmas DECimal 25

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