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# Messed Up Math

## Question

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

## 23 answers to this question

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Need a hint?

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yeh mon, lay it on us... [it's not octal at least ... but what?]

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You got the hint (bases)

Any more would be giving it away

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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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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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You got it brhan! Except x is 5

5(5) = 25

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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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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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NEW PROBLEM

***************

60-(3•x) = 2§

2+x = 10

what is x? and what number does § represent?

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NEW PROBLEM

***************

60-(3•x) = 2§

2+x = 10

what is x? and what number does § represent?

Exactly. It is much better.

Well, I think the digits on the left (and the operations applied) are in base 10, while those on the right are in base 12.

So x=10; and §=6.

60-30 = 30 which is 26 in base 12.

2+10 = 12 which 10 in base 12.

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you are wrong. "10" in any base higher than 10 has to be represented by a symbol. In base 12, 12 is 10, not 10. You should read up on your bases!

The left is base 10 of course.

But you were CLOSE with your guess of base 12 on the right

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you are wrong. "10" in any base higher than 10 has to be represented by a symbol. In base 12, 12 is 10, not 10. You should read up on your bases!

The left is base 10 of course.

But you were CLOSE with your guess of base 12 on the right

Well, that is obvious ... by 10, I mean (9+1) in base higher than 9 (and of course 12 > 9). Usually it is represented by symbol A.

BTW, I said §=26. It is just a typo. I have edited it now : §=6.

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you are wrong

But you were CLOSE with your guess of base 12 on the right

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60-(3•x) = 2§

2+x = 10

i'll tell you what § is: it is 10

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60-(3•x) = 2§

2+x = 10

i'll tell you what § is: it is 10

You got it wrong, bro .... Whatever operation u may apply and whichever base u use, you cannot get § to be 10. Now, u cannot say 2§ is to mean 2 multiplied by § b/c u used • as multiplication operator.

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Barely noticed, the bell rings; and the opponents

sit quietly in their corners while their seconds

attend quickly to the cuts and bruises.

The bell rings for Round 4 ....

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So x=10; and §=6.

60-30 = 30 which is 26 in base 12.

2+10 = 12 which 10 in base 12.

Seems to me that brhan's answer is valid. Why is it being rejected?

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because § is 10, and a symbol has to be used for numbers higher than 9 in bases higher than 10. He used base 12 and he said 10 outright which would be 12 not 10, a symbol (I chose § for this) would have to represent that. Anyway this is the answer (tho his answer may be right, there might be multiple answers, but not with § as ten)

60-(3•x) = 2§

2+x = 10

i'll tell you what § is: it is 10

base 11.

x=9

9+2 = 11 = 10

60-(3•9) = 60-27 = 33. In base 11, 33 is 30... oops! I meant it to be 32 not 33, and 32 is 2§ in base 11. woops!

I guess the correct problem would be:

59-(3•x) = 2§

2+x = 10

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base 11.

x=9

9+2 = 11 = 10

60-(3•9) = 60-27 = 33. In base 11, 33 is 30... oops! I meant it to be 32 not 33, and 32 is 2§ in base 11. woops!

I guess the correct problem would be:

59-(3•x) = 2§

2+x = 10

I assumed '§' as a place holder for a digit, b/c u didn't specify in the question that '§' is actually a symbol for unknown base.

BTW, the question has a unique solution -- and my solution is the correct one .

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Yep mine would have been right if 60 was 59, again, sorry for the error

and § was a placeholder for a digit.. since in a base higher than 10, the number 10 has to be represented by 1 digit. Normally its A, but I didnt want it to be that easy so I made it a random symbol.

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NEW PROBLEM

***************

60-(3•x) = 2§

2+x = 10

what is x? and what number does § represent?

x is 8, §is 18

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60-(3•x) = 2§

2+x = 10

what is x? and what number does § represent?

x is 8, §is 18

2§ does not mean that 2 multiplied by §, b/c • was already used for multiplication symbol.

§ is a place holder for a digit. In addition, the numbers on the right and left hand sides are of different bases.

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brhan is correct, and the (only) correct answer has already been given (by him, mine would have been right if not for that typo )

I plan on making another topic like this soon sometime so you can answer then

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