Find the smallest number comprised of only 3’s and 7’s which fits the following conditions:
1) It has at least one 3;
2) It has at least one 7;
3) It is divisible by 3;
4) It is divisible by 7;
5) The sum of its digits is divisible by 3;
6) The sum of its digits is divisible by 7.
(In reply to
the computer doing the trial and error by Charlie)
Close but no cigar...
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<TR style="HEIGHT: 12.75pt" height=17>
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How to solve
3*7 = 21 but no number of figures of 7's and 3's solve it
so 21*2 = 42, so how many 3's and 7's can make 42 and devive by 7's and 3's (i.e. 21 + 21)
so 7 3's and 3 7's
Make an order and the last digit MUST be 3.
3333337773 added totals 42
/3 = 1111112591
/7 = 476191110
Took about 1 hour with pen and paper.

Posted by stewart
on 20060410 07:23:03 