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 Subject: RE: Try to solve this. Author: tpowers Date: Aug 18 2004
C'mon people. . . let's try to solve these!

OK, I'll start with #3 because that type of question is one of my favorites.

1111. . . (n digits) is never prime if n is composite.  That is because, if you
can factor n as p * q (p and q not equal to n or 1), you can split up the 1111.
. . into p chunks of length q; one of these chunks will be a factor.  This
should be clear if you try doing long division on 1111. . . because every q
digits you will have a "1" (the chunk goes in), and, since q goes into n evenly,
you won't have any non-chunked digits.  You end up generating factors of 1111.
. ., namely, 1 (q times) and 1 (p times).

For example, 91 = 7 * 13, so you could divide 1 (91 times) by 1 (7 times) or 1
(13 times).

By the way, could you please re-state question two?  I couldn't understand
what it meant when I was doing the rest of the problems.

Thanks for the problems.

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