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Messed Up Math


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23 replies to this topic

#1 unreality

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Posted 22 September 2007 - 07:26 PM

until we get a Math forum, the math riddles go here

if 22+7 is 41

and 22+5 is 36

what is x?

5x = 19
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#2 unreality

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Posted 22 September 2007 - 10:57 PM

Need a hint?
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#3 bonanova

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Posted 22 September 2007 - 11:17 PM

yeh mon, lay it on us... [it's not octal at least ... but what?]
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
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#4 unreality

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Posted 23 September 2007 - 12:46 AM

You got the hint (bases)

Any more would be giving it away
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#5 bonanova

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Posted 23 September 2007 - 05:31 AM

You got the hint (bases)

There are digits as high as 9, so the basis would have to be 10 or greater.
But you can't go from twenty-something to forty-something by adding 7 with a basis that high.

I'm curious to see how this turns out.
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#6 brhan

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Posted 23 September 2007 - 02:33 PM

well, looks like base 7:

22+7 is 29 .... (41 in base 7)

22+5 is 27 .... (36 in base 7)

5x = 19.

19 in base 7 is 25 ..... can we say then x=2, (though the positions are transposed)
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#7 unreality

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Posted 23 September 2007 - 04:59 PM

You got it brhan! Except x is 5

5(5) = 25
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#8 brhan

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Posted 23 September 2007 - 10:06 PM

You got it brhan! Except x is 5

5(5) = 25



Ok ... but it would have been better to put the multiplication operator between 5 and x -- b/c otherwise it seems concatenation.
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#9 unreality

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Posted 23 September 2007 - 10:55 PM

Ahh you thought it was 5x as in 52 or something? I gotcha. Like an unknown digit as opposed to multiplication. Sorry. How's this?

5•x = 19

or this?

5*x = 19
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#10 unreality

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Posted 23 September 2007 - 11:02 PM

NEW PROBLEM
***************

60-(3•x) = 2§

2+x = 10

what is x? and what number does § represent?
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