

Subject:
Riddle
Category: Miscellaneous Asked by: aj9989ga List Price: $2.00 
Posted:
09 May 2006 23:07 PDT
Expires: 08 Jun 2006 23:07 PDT Question ID: 727192 
A drawer contains a number of red and blue socks. If I pull two out at random, then their chance of being a red pair is one half and their chance of being a blue pair is one twelfth. How many socks are in the drawer? How many of each color? 

Subject:
Re: Riddle
Answered By: dencoga on 10 May 2006 00:01 PDT Rated: 
Howdy aj9989ga, Bryan (probonopublicoga) speaks a certain truth in his comment, as there are an odd number of red and blue socks in the drawer. One of "Ken's Puzzle of the Week" has the solution to your riddle. http://www.ken.duisenberg.com/potw/archive/arch00/000228sol.html "85 red, 35 blue" The above page also provides the formula that we need to prove this. "... We have to find a and b integers representing respectively the numbers of red and blue socks such as: a*(a1)/(a+b)*(a+b1) = p (1) b*(b1)/(a+b)*(a+b1) = q (2) ..." If we take the first formula for the red socks, we get: 85*84/120*119 = 7140/14280 = 1/2 We can then apply the second formula to prove the blue socks solution: 35*34/120*119 = 1190/14280 = 1/12 If you need any clarification, please feel free to ask. Search strategy: Google search on: red blue socks drawer ://www.google.com/search?q=red+blue+socks+drawer Looking Forward, dencoga  Google Answers Researcher 
aj9989ga rated this answer: and gave an additional tip of: $1.00 

Subject:
Re: Riddle
From: probonopublicoga on 09 May 2006 23:25 PDT 
This is impossible to answer because there is always at least one sock missing. 
Subject:
Re: Riddle
From: dencoga on 10 May 2006 11:47 PDT 
Thanks for the 5 star rating and tip, aj9989ga. Looking Forward, dencoga  Google Answers Researcher 
If you feel that you have found inappropriate content, please let us know by emailing us at answerssupport@google.com with the question ID listed above. Thank you. 
Search Google Answers for 
Google Home  Answers FAQ  Terms of Service  Privacy Policy 