Einstein's Riddle

Erik
Erik
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RE: If you follow the laws

Message 64360 in response to message 64359

Quote:
If you follow the laws of mathematics, 1-2*3-4+5*6+7+8*9=100
One should always calculate multiplication and division before doing addition and subtraction. If you want to make exceptions from this priority, then you have to use algebraic expressions "()"
Your example would look like this: (((1-2)*3-4+5)*6+7+8)*9=27
If you were looking for a solution that calculates it from left to right then this is your answer.
(((((((1+2)*3)+4)+5)*6)-7)+8)-9=100


Yes, I was looking for a left to right calculation. I apologize for not being clearer in my instructions. Thank you also for the remedial algebra; it has been a long time since high school.

Erik
Erik
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Congratulations to Ziran for

Congratulations to Ziran for solving the last puzzle!

W7QU
W7QU
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RE: I came across a riddle

Quote:

I came across a riddle that supposedly Albert Einstein wrote early in the last century and claimed that 98% of the world population would not be able to solve it.

It doesn't use word play, just logic. If you believe you have the answer, post your answer in BBCode tagged to size 2 so it won't spoil it for others.
______________________________________________________
1. In a street there are five houses, painted five different colours.
2. In each house lives a person of a different nationality.
3. Each homeowner drinks a different kind of beverage, smoke different brands of cigarettes and keeps a different pet.
4. The Brit lives in a red house.
5. The Swede keeps dogs as pets.
6. The Dane drinks tea.
7. The green house is next to, and on the left of the white house.
8. The owner of the green house drinks coffee.
9. The person who smokes Pall Mall rears birds.
10. The owner of the yellow house smokes Dunhill.
11. The man living in the center house drinks milk.
12. The Norwegian lives in the first house.
13. The man who smokes Blends lives next to the one who keeps cats.
14. The man who keeps horses lives next to the man who smokes Dunhill.
15. The man who smokes Blue Master drinks beer.
16. The German smokes Prince.
17. The Norwegian lives next to the blue house.
18. The man who smokes Blends has a neighbor who drinks water.

Who owns the fish?


Chipper Q
Chipper Q
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RE: Using addition,

Message 64363 in response to message 64354

Quote:
Using addition, subtraction, multiplication or division make the numbers "1 2 3 4 5 6 7 8 9" equal 100. The numbers have to be resolved in the same chronological order from lesser to greater (1+2*3+4...)


Been a long day, got a late start with this one, not sure about this solution:
(1+2+3+4)*5*(-6+7-8+9) = 100, but I think I wedged in an extra operator with the 6...

MAGIC Quantum Mechanic
MAGIC Quantum M...
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I just stopped by to read all

Message 64364 in response to message 64363


I just stopped by to read all of your tiny little answers and comments.......I always enjoy a bit of non-fictional writing no matter how minute

Erik
Erik
Joined: 14 Feb 06
Posts: 2815
Credit: 2645600
RAC: 0

RE: RE: Using addition,

Message 64365 in response to message 64363

Quote:
Quote:
Using addition, subtraction, multiplication or division make the numbers "1 2 3 4 5 6 7 8 9" equal 100. The numbers have to be resolved in the same chronological order from lesser to greater (1+2*3+4...)

Been a long day, got a late start with this one, not sure about this solution:
(1+2+3+4)*5*(-6+7-8+9) = 100, but I think I wedged in an extra operator with the 6...

The answer I was looking for would require the use of positive integers. But nice try! :)

Erik
Erik
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RE: I just stopped by to

Message 64366 in response to message 64364

Quote:


I just stopped by to read all of your tiny little answers and comments.......I always enjoy a bit of non-fictional writing no matter how minute

:D

Erik
Erik
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I'm going out of state for a

I'm going out of state for a couple days for work so I won't be able to keep up with this thread. I'll answer any posts ASAP when I get back.

Chipper Q
Chipper Q
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RE: RE: RE: Using

Message 64368 in response to message 64365

Quote:
Quote:
Quote:
Using addition, subtraction, multiplication or division make the numbers "1 2 3 4 5 6 7 8 9" equal 100. The numbers have to be resolved in the same chronological order from lesser to greater (1+2*3+4...)

Been a long day, got a late start with this one, not sure about this solution:
(1+2+3+4)*5*(-6+7-8+9) = 100, but I think I wedged in an extra operator with the 6...

The answer I was looking for would require the use of positive integers. But nice try! :)


Hmm, the 6 and 8 are both positive integers, and I used subtraction with them. :)
It doesn't preserve the ascending order, but my solution could be written: (1+2+3+4)*5*(7-6-8+9). Only positive integers used.

I do like the solution provided by Ziran better, tho'. I noticed you got 27 when performing the operations sequentially (instead of multiplication before addition), so did you by chance have a different answer than Ziran's for this one?

Thanks for another fun one! :)

::wonders about bonus points for using multiplication only twice::

Erik
Erik
Joined: 14 Feb 06
Posts: 2815
Credit: 2645600
RAC: 0

RE: RE: RE: RE: Using

Message 64369 in response to message 64368

Quote:
Quote:
Quote:
Quote:
Using addition, subtraction, multiplication or division make the numbers "1 2 3 4 5 6 7 8 9" equal 100. The numbers have to be resolved in the same chronological order from lesser to greater (1+2*3+4...)

Been a long day, got a late start with this one, not sure about this solution:
(1+2+3+4)*5*(-6+7-8+9) = 100, but I think I wedged in an extra operator with the 6...

The answer I was looking for would require the use of positive integers. But nice try! :)


Hmm, the 6 and 8 are both positive integers, and I used subtraction with them. :)
It doesn't preserve the ascending order, but my solution could be written: (1+2+3+4)*5*(7-6-8+9). Only positive integers used.

I do like the solution provided by Ziran better, tho'. I noticed you got 27 when performing the operations sequentially (instead of multiplication before addition), so did you by chance have a different answer than Ziran's for this one?

Thanks for another fun one! :)

::wonders about bonus points for using multiplication only twice::

Congratulations to you, Chipper Q, for solving the problem!

I apologize Chip, I could have sworn I saw a negative number in there (-7?!). I think the brackets got me confused. Who knows, it doesn't take much. I just redid the calculation and you are correct.

Actually I was going to ask another question on this problem putting a twist on it with using only two of the four operands [+,-,*,/] (I'm not sure if operands is the correct word, it is the only one that comes to mind right now. I just got back from my trip out east and it's past my bedtime). An answer would have been (at least one anyway...) 1+2+3+4+5+6+7+(8*9). I think I learned my lesson on this thread... well, a couple it seems.

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