Without using any arithmetical symbols (+, -, *, /, or similar; other math symbols; decimal comma or periods; letters; even parentheses) or, in short, anything but the digits, build a number with the digits 1, 3, 5, 7 and 9, that is equal to a number built with the digits 2, 4, 6 and 8 (each digit used once and only once).

Note: This is not a trick. It was extracted from a book edited by Angela Dunn, a mathematician who gathered problems that appeared in many scientific periodical revues!

(In reply to re: Different Approach by pcbouhid)

I think Lisa is may also be thinking about how to use calculator digits, such when the display is inverted, produces a word (or something in that line of thought)

Trick?  Well?  The 4x4 square did embody one, I'll forgive her the thought.

But ...  there still appears to be a .. dare I say it? ... trick.  I think that 'owl'  had a good thought. 

If we only have exclusive use of the digits, then it seems to me that either numerals (within a given bases)  or numerals raised to a power,  .... and then .. we might combine both thoughts, has possibilities.

Powers!  With the Odd digit set, no matter what I take as my base, the others become my power index, and so give an odd numeral.   The same process with the even digits yields ... even.
NO Joy.

Is there a configuration where an odd numeral A, raised to the power  Q within base system X equates to an even numeral which is similarly structured?

Posted by brianjn on 2005-07-01 14:25:12