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Non BG Related Probability Problem - for fun

Posted By: John McDonald
Date: Tuesday, 4 May 2010, at 5:47 p.m.

Had to prove this one a long time ago in University. You can look it up on the internet but it is more interesting to guess the number.

The Birthday Problem

Q. By randomly selecting people, how many individuals do you need before there is a greater than 50% probability that two of them will have the same birthday ?

Bonus -- How many do you need to have a greater than 99%

Will post the answer in a day or so.

Messages In This Thread

• Non BG Related Probability Problem - for fun
  John McDonald -- Tuesday, 4 May 2010, at 5:47 p.m.
  • Non BG Related Probability Problem - for fun
    Frank Berger -- Tuesday, 4 May 2010, at 6:59 p.m.
  • Non BG Related Probability Problem - for fun
    Nack Ballard -- Tuesday, 4 May 2010, at 8:49 p.m.
  • Non BG Related Probability Problem - for fun
    W Womack -- Tuesday, 4 May 2010, at 9:02 p.m.
  • Partial spoiler
    Timothy Chow -- Tuesday, 4 May 2010, at 9:05 p.m.
    • Partial spoiler
      W Womack -- Tuesday, 4 May 2010, at 9:55 p.m.
      • Partial spoiler
        Timothy Chow -- Tuesday, 4 May 2010, at 10:35 p.m.
        • Partial spoiler
          Bob Koca -- Tuesday, 4 May 2010, at 11:46 p.m.
  • Non BG Related Probability Problem - Answer
    John McDonald -- Wednesday, 5 May 2010, at 3:57 p.m.
    • Non BG Related Probability Problem - Answer
      Rich Munitz -- Wednesday, 5 May 2010, at 4:29 p.m.
      • Non BG Related Probability Problem - Answer
        Timothy Chow -- Wednesday, 5 May 2010, at 5:36 p.m.
        • Non BG Related Probability Problem - Answer
          Rich Munitz -- Wednesday, 5 May 2010, at 6:40 p.m.
        • Non BG Related Probability Problem - Answer
          W Womack -- Wednesday, 5 May 2010, at 7:26 p.m.