**Edited by BMAD, 08 August 2013 - 02:12 AM.**

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Guest Message by DevFuse

# i am thinking of a number...

Started by BMAD, Aug 08 2013 02:10 AM

5 replies to this topic

### #1

Posted 08 August 2013 - 02:10 AM

I am thinking of an integer n with 0 <= n <= 15. To figure out what number I'm thinking of, you can ask me 7 yes-or-no questions --questions that can only be answered with either "yes" or "no". The questions must be independent of each other, their answers, and the order in which they are answered. (So you can't ask a question like, "if the answer to the previous question was "yes", then is n larger than 10, otherwise is n even?") When you ask me your seven questions, I am allowed to LIE about at most one of the answers. What seven questions can you ask to determine n?

### #2

Posted 08 August 2013 - 04:12 AM

Spoiler for I don't think it's possible?

### #3

Posted 08 August 2013 - 02:12 PM

Spoiler for ugly solution

### #4

Posted 08 August 2013 - 05:54 PM Best Answer

Spoiler for

### #5

Posted 08 August 2013 - 07:30 PM

- does the number have 2 digits?
- is the number a prime number?
- is the sun of the digits greater than 3?
- is the number divisible by 3?
- is the number a factor of 2?
- is the number greater than 6?
- is the number 0?

### #6

Posted 14 August 2013 - 12:42 PM

Spoiler for solution

**Edited by brob26, 14 August 2013 - 12:44 PM.**

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