FlasherMXer Posted March 7, 2003 Posted March 7, 2003 [url]http://www.cyberglass.co.uk/assets/Flash/psychic.swf[/url] You're probably aware of the trick to find whether a number is divisible by 9 - if it's divisible by 9, so is the sum of its digits. The same thing works for divisibility by 3. For example: 12345's digits add up to 1+2+3+4+5 = 15 which is divisible by 3, so 12345 is divisible by 3 (it's 4115×3). 10746's digits add up to 1+7+4+6 = 18 which is divisible by both 3 and 9, so 10746 is divisible by both 3 and 9 (it's 3582×>3 or 1194×9). It's possible to prove that this will always work - one possible proof is: Let m be an n-digit number, and its digits in reverse order be d0, d1 -Okayzaki
eleanor Posted March 8, 2003 Posted March 8, 2003 Just when I get out of school.... Uh.. ::tries to comprehend and passes out:: Right...what's the point of this again? ^__^ j/k
DeathKnight Posted March 8, 2003 Posted March 8, 2003 [color=crimson]It started with the number 9 and went straight downhill from there.[/color]
Mitch Posted March 8, 2003 Posted March 8, 2003 [color=red] Uh...I already knew all of that. And I know next to nothing about Math. O-o So this thread is rather pointless. So I'm saying please don't make a pointless thread like this again. This is just a warning. This thread will self destruct in one second. Please stand back. [i]Do not[/i] post a pointless thread like this again. If you've got a brain in the head that isn't already been smoked away, then please consider the validity of something before pointlessly posting it. Good day. :)[/color]
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