# Quick Puzzle **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [August 20, 2002, 7:35pm UTC](https://boards.straightdope.com/t/quick-puzzle/124777 "2002-08-20T19:35:46Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![Gomez](https://avatars.discourse-cdn.com/v4/letter/g/d78d45/32.png) [@Gomez](https://boards.straightdope.com/u/Gomez)\ **Post date:** [August 20, 2002, 7:35pm UTC](https://boards.straightdope.com/t/quick-puzzle/124777/1 "2002-08-20T19:35:46Z")
**Doorway to Death** One morning you wake up to find yourself in a large room with three exits and no apparent entrance (don’t ask why, you just do). You don’t remember how you managed to get in there but suffice to say you are in there now and want to get home in time for dinner. You look at the three exits and note that they are all completely identical but are numbered 1, 2 and 3. You also notice a rather menacing looking guard standing in your way, blocking your path to the doors. Naturally, you inquire as to which door to take. The guard replies _“One of these doors leads to salvation, the other two lead to damnation. Three questions you will get to try, But be forewarned, on two I’ll lie. Don’t ask why, for I just will. You’ll have to use your wits and skill”_ Hmmm, okaaay. You have had better starts to the day than this. Still, you’ve got to play the cards you’re dealt. Which three questions will ensure you safe passage to the outside world? ---
**Author:** ![Smashed\_Ice\_Cream](https://avatars.discourse-cdn.com/v4/letter/s/ed8c4c/32.png) [@Smashed\_Ice\_Cream](https://boards.straightdope.com/u/Smashed_Ice_Cream)\ **Post date:** [August 20, 2002, 8:02pm UTC](https://boards.straightdope.com/t/quick-puzzle/124777/2 "2002-08-20T20:02:11Z")
Ask him twice something like “are you a man?” by his answers you’ll know if the third question he’ll answer truthfully or not. Then; If it will be the truth, ask him which door is safe. If it will be a lie: ask him which door leads to death. Take whatever door he points at. ---
**Author:** ![Gomez](https://avatars.discourse-cdn.com/v4/letter/g/d78d45/32.png) [@Gomez](https://boards.straightdope.com/u/Gomez)\ **Post date:** [August 20, 2002, 8:20pm UTC](https://boards.straightdope.com/t/quick-puzzle/124777/3 "2002-08-20T20:20:51Z")
Sorry, I should have specified that you can only ask YES or NO questions. Curse the lack of an edit function. Good try though. That would definately have worked if you’d not been restricted to Yes or No questions. Sorry 'bout that. ---
**Author:** ![donkeyoatey](https://avatars.discourse-cdn.com/v4/letter/d/e47c2d/32.png) [@donkeyoatey](https://boards.straightdope.com/u/donkeyoatey)\ **Post date:** [August 21, 2002, 1:07am UTC](https://boards.straightdope.com/t/quick-puzzle/124777/4 "2002-08-21T01:07:46Z")
Ask him twice " does 2+2 =4", then what **Smashed Ice Cream** said. ---
**Author:** ![donkeyoatey](https://avatars.discourse-cdn.com/v4/letter/d/e47c2d/32.png) [@donkeyoatey](https://boards.straightdope.com/u/donkeyoatey)\ **Post date:** [August 21, 2002, 1:12am UTC](https://boards.straightdope.com/t/quick-puzzle/124777/5 "2002-08-21T01:12:12Z")
On second reading, that’s the same as **SMI** ’s answer, why is she wrong? “are you a man” \*\*is \*\* a yes or no question, isn’t it? ---
**Author:** ![donkeyoatey](https://avatars.discourse-cdn.com/v4/letter/d/e47c2d/32.png) [@donkeyoatey](https://boards.straightdope.com/u/donkeyoatey)\ **Post date:** [August 21, 2002, 1:15am UTC](https://boards.straightdope.com/t/quick-puzzle/124777/6 "2002-08-21T01:15:01Z")
Okay, okay ignore both of my posts:o ---
**Author:** ![Gomez](https://avatars.discourse-cdn.com/v4/letter/g/d78d45/32.png) [@Gomez](https://boards.straightdope.com/u/Gomez)\ **Post date:** [August 21, 2002, 11:20am UTC](https://boards.straightdope.com/t/quick-puzzle/124777/7 "2002-08-21T11:20:40Z")
I thought this would be long gone by now. Anyone want a hint? ---
**Author:** ![woolly](https://avatars.discourse-cdn.com/v4/letter/w/ebca7d/32.png) [@woolly](https://boards.straightdope.com/u/woolly)\ **Post date:** [August 21, 2002, 1:28pm UTC](https://boards.straightdope.com/t/quick-puzzle/124777/8 "2002-08-21T13:28:31Z")
Q1 Does door #1 lead to salvation? Q2 Do I have 2 questions left? Q3 Does door #2 lead to salvation? ---
**Author:** ![postcards](https://avatars.discourse-cdn.com/v4/letter/p/8e8cbc/32.png) [@postcards](https://boards.straightdope.com/u/postcards)\ **Post date:** [August 21, 2002, 2:17pm UTC](https://boards.straightdope.com/t/quick-puzzle/124777/9 "2002-08-21T14:17:08Z")
> [@](#): > > Naturally, you inquire as to which door to take. The guard replies: Does this count as the first question? If it is, how can you be sure if the subsequent verse is the truth? Maybe all three dorrs lead to salvation! Or not. ---
**Author:** ![Gomez](https://avatars.discourse-cdn.com/v4/letter/g/d78d45/32.png) [@Gomez](https://boards.straightdope.com/u/Gomez)\ **Post date:** [August 21, 2002, 5:07pm UTC](https://boards.straightdope.com/t/quick-puzzle/124777/10 "2002-08-21T17:07:36Z")
The subsequent verse _is_ the truth. Your first inquiry did _not_ count as one of your questions. **Woolly**. I don’t understand how your solution works. Let’s assume it’s door one and the guard answers your questions thusly: Q1 Does door #1 lead to salvation? - YES (truth) Q2 Do I have 2 questions left? - NO (lie) Q3 Does door #2 lead to salvation? - YES (lie) How would you know whether or not to take door 1? ---
**Author:** ![armedmonkey](https://avatars.discourse-cdn.com/v4/letter/a/d6d6ee/32.png) [@armedmonkey](https://boards.straightdope.com/u/armedmonkey)\ **Post date:** [August 21, 2002, 7:16pm UTC](https://boards.straightdope.com/t/quick-puzzle/124777/11 "2002-08-21T19:16:13Z")
I think I got it, the trick is to ask the same question twice. Q1 Does either door A or B lead to salvation? Q2 Does either door A or B lead to salvation? Q3 Does door A lead to salvation? YYY - impossible outcome YYN - door C YNY - door B NYY - door B YNN - door A NYN - door A NNY - door A NNN - door B ---
**Author:** ![Gomez](https://avatars.discourse-cdn.com/v4/letter/g/d78d45/32.png) [@Gomez](https://boards.straightdope.com/u/Gomez)\ **Post date:** [August 21, 2002, 9:42pm UTC](https://boards.straightdope.com/t/quick-puzzle/124777/12 "2002-08-21T21:42:17Z")
Wow, good work Beeblebrox. It’s totally different from the answer I’ve intended but I can’t spot a flaw in your solution so full credit goes to you. For the record, my answer was: Q1: Will you answer this question truthfully Q2: Does door 1 lead to salvation Q3: Does door 2 lead to salvation? Whatever the guard answers for Q1 will be a truthful answer. Therefore the answers to Q2 & Q3 are both lies. If the guard answers No to Q2 then door 1 is correct, if the guard answers Yes to Q2 but No to Q3 then door 2 is right and if he answers Yes to both 2 & 3 then door 3 is right. Hope you liked the puzzle.