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#1 User is offline   rookie1ja Icon

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Posted 31 March 2007 - 05:08 PM

No. 18 - Back to the Cryptograms and Algebra Puzzles
Replace the same characters by the same numerals so that the mathematical operations are correct.
AL = LEBKA



Spoiler for Solution:
No. 18 - solution
57 = 78125

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#2 User is offline   guderman Icon

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Posted 26 September 2007 - 09:11 PM


two possible answers here.

we realize that the number has to be at least 5 digits long, so we need to look for a power that has five digits...

3^9 = 19683,

which is too small.

the next one in the neighborhood is 4^8, which is also too small, and without even bothing to do the next multiplication, one can see that 4^9 would have too many digits.

that brings us to...

5^7 = 78125,

which is a correct answer. But is it the only one? 6^6 is slightly too small (and besides, one can make the reasonable assumption that different letters mean unique numbers). 7^5 is too small while 7^6 is too big. 8^5 is too small, and the next higher power will have too many digits. That brings us to the last possibility, which is 9^5 = 59049, which is a possibility, but only if you allow different letters to mean the same digit. I am assuming that such is not allowed, which would negate this option, so that means that 5^7 is the correct answer.
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#3 User is offline   BoilingOil Icon

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Posted 26 September 2007 - 10:51 PM

Quote


.....

5^7 = 78125,

.....


I see no way to improve on your mathematic skills here, guderman. And I'm known to do such things sometimes
Very well done.


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#4 User is offline   cpotting Icon

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Posted 27 September 2007 - 03:10 PM

9 and 5 also work, if you allow multiple letters to represent the same digit [a reasonable assumption since a) the problem did not specify otherwise, and B) there are 26 letters and only 10 digits].

L = 5
E = 9
B = 4
K = 0
A = 9
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#5 User is offline   BoilingOil Icon

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Posted 27 September 2007 - 05:06 PM

Quote

9 and 5 also work, if you allow multiple letters to represent the same digit [a reasonable assumption since a) the problem did not specify otherwise, and B) there are 26 letters and only 10 digits].

L = 5
E = 9
B = 4
K = 0
A = 9


Well, actually, several people try to pose this assumption because it wasn't explicitly excluded beforehand. Usually, this kind of problem would only be a real puzzle, if we assume that each DIFFERENT letter actually signifies a DIFFERENT digit. Otherwise, what would be the point?

And even if your assumption was allowable, your answer would still be wrong, because you switched the 0 and the 4

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#6 User is offline   bob Icon

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Posted 07 October 2007 - 05:39 PM

l2 is the equation 9 divided by 3.5678324 and then multiplied by 28. divid this by l and then plug in a as a variable. once you solve for a then just simplifly and divided your decimal or fraction by 9 again.
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#7 User is offline   cpotting Icon

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Posted 09 October 2007 - 05:07 PM

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And even if your assumption was allowable, your answer would still be wrong, because you switched the 0 and the 4

BoilingOil

oops
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