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# Messed Up Math #2

9 replies to this topic

### #1 unreality

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Posted 02 October 2007 - 09:36 PM

Some Basic Things
~~~~~~~~~~~~~~~~~~~
For bases higher than 10:
A = 10
B = 11
C = 12 and so on
...
Z = 35 for base 36

~~~~~~~~~~~~~~~~~~~~~~~~~~~
Left sides of equations are almost always gonna be calculations in base 10, resulting
in the result on the other side
~~~~~~~~~~~~~~~~~~~~~~~~~~~

Lets say x=5

3x2 is the number 352, not 3•2 and not 3•5•2

4x is 45, not 4•x

Thus if it is a digit placeholder, it's gonna be a single digit
Let's say x is 9 and you have xx, that would be 99

However if its a variable, it could be any number, like 7,265.384
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

4x+2 = xx

1. What is x?
2. What base is the right side in?

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### #2 Martini

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Posted 02 October 2007 - 09:59 PM

This type of math problem is not a brain teaser in the classical sense.

Post these type of problems in 'Others' from now on.
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### #3 brhan

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Posted 03 October 2007 - 04:00 PM

Some Basic Things

4x+2 = xx

1. What is x?
2. What base is the right side in?

X is 6, which makes the left hand side to be 48.

48 in base 7 is 66.
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### #4 unreality

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Posted 03 October 2007 - 08:52 PM

You're quick!
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### #5 unreality

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Posted 06 October 2007 - 06:32 PM

1x•x/2= C

What is x?
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### #6 brhan

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Posted 06 October 2007 - 07:01 PM

(10+X) (X/2) = 12 (in base 10)
==> X^2+10X-24 = 0
X = -12 or X = 2.
As X is a place holder for a digit (should be b/n 0 and 9), X = 2.

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### #7 unreality

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Posted 07 October 2007 - 04:25 AM

Yep.

12*1=12

And btw, X could be higher than 9 if the base is higher than base 10, even tho its not in this case, it can be (look at "C"). Obviously a single digit cant be negative unless thats the only digit in the number, so it has to be 2
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### #8 brhan

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Posted 07 October 2007 - 01:54 PM

And btw, X could be higher than 9 if the base is higher than base 10, even tho its not in this case, it can be (look at "C"). Obviously a single digit cant be negative unless thats the only digit in the number, so it has to be 2

Well, not in your case. Because you already made it clear that the number in the left side is in base 10. You cannot have "C" or whatever symbol in base 10.
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### #9 unreality

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Posted 07 October 2007 - 02:16 PM

I know, that's what i said "not in this case" but it is possible to be a placeholder for a higher numbe, like A,B,C,etc

how bout u give me a problem now? lol you're better at this than me
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### #10 brhan

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Posted 08 October 2007 - 01:37 PM

I enjoyed your puzzles ... currently, I don't have such puzzles, but will do something in the future.
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