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# Elevator

14 replies to this topic

### #11 lenzvlt

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Posted 06 November 2011 - 02:45 PM

Does serious must mean you know you are also absolutely right?
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### #12 mewminator

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Posted 06 November 2011 - 09:21 PM

7 buttons? isn't this an 8 story building?
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### #13 famous1304

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Posted 17 August 2013 - 12:00 PM

Spoiler for Spoiler

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### #14 bhramarraj

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Posted 31 August 2013 - 04:51 PM

Actually, unless I have misread the solution, normdeplume's submission results in 4 correct floors (B, 4, 5, 7), not 3 as required by the author. One that might be a better fit would be:

8 -- 4 (x0.5)
7 -- 1 (simple mismatch)
6 -- 3 (x0.5)
5 -- 5 (OK)
4 -- 8 (x2.0)
3 -- 6 (x2.0)
2 -- 2 (OK)
1 -- 7 (simple mismatch)
B -- B (OK)

This solution also has the added benefit of being rather symmetrical (if that appeals to you...) since doubles and halves line up nicely.

Button 1 does not work correctly -> It will lead to 1/2 floor or 2nd floor. Must be 2nd floor.
Therefore button 2 does not work correctly -> It will lead to 1st floor or 4th floor. If it does not lead to 1st floor, no other button can. Must be 1st floor.
If so, how do we get to 4th floor? Can not be from button 2, cannot be from button 8 (no such button). It must be from button 4.
Out of 3 even button 2,4,6, button 4 works correctly, hence button 6 must lead to 3rd floor.
Therefore button 3 does not work correctly -> It will lead to 6th floor.
We come to the solution drawn by normdeplume.
Nice puzzle, thanks

OP clearly indicates ---- "Three of the seven buttons work correctly; two take one to a floor with a number twice that of the floor to which they should; and two take on to a floor with a number half that of the floor to which they should." Where is the confusion?

normdeplume's answer is correct & excelently explained by someids.

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### #15 kestrelknight

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Posted 01 September 2013 - 08:40 AM

WHY WE NEED TO GET INTO LOGIC OR MATHS TO SOLVE THIS PROBLEM?
IT IS INDICATED THAT WHEN ELEVATOR IS AT BASEMENT LEVEL THE SWITCHES DOES NOT WORK PROPERLY

THIS MEANS AT ALL OTHER LEVELS THEY WILL WORK PROPERLY.

YOU MAY PRESS ANY BUTTON AT BASEMENT LEVEL TO TAKE AT ANY OTHER LEVEL AND ALL JOURNEY FROM THAT LEVEL WILL TAKE YOU TO CORRECT LEVEL!!!

Hush, you. There are geniuses at work here. Not me, though. I'm not fond of formulas, Math, and all that stuff.

Also, shouting is antisocial.

And you make it sound like one elevator shaft will have like a billion elevators in it. Which wouldn't actually work.

Go troll somewhere else. I know I shouldn't be feeding you, but I couldn't help it.

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