Search

The three envelopes problem
 Posted: 18 July 2012 12:56 PM [ Ignore ]
Sr. Member
Total Posts:  9301
Joined  2006-08-29

Just kidding!  :coolgrin:

 Profile

 Posted: 18 July 2012 04:37 PM [ Ignore ]   [ # 1 ]
Moderator
Total Posts:  5551
Joined  2010-06-16

Thank goodness.  I was afraid that we’d generate another mega-thread. :snake: :lol:

Occam

[ Edited: 19 July 2012 10:00 AM by Occam. ]
Signature

Succinctness, clarity’s core.

 Profile

 Posted: 19 July 2012 12:53 AM [ Ignore ]   [ # 2 ]
Sr. Member
Total Posts:  5255
Joined  2007-08-31

Three envelopes are presented in front of you by an interviewer. One contains a job offer, the other two contain rejection letters. You pick one of the envelopes. The interviewer then shows you the contents of one of the other envelopes, which is a rejection letter. The interviewer now gives you the opportunity to switch envelope choices. Should you switch?

The answer is yes.  Say your original pick was envelope A.  Originally, you had a 1/3 chance that envelope A contained the offer letter.  There was a 2/3 chance that the offer letter was either in envelope B or C.  If you stick with envelope A, you still have the same 1/3 chance.  Now, the interviewer eliminated one of the envelopes (say, envelope B), which contained a rejection letter.  So, by switching to envelope C, you now have a 2/3 chance of getting the offer and you’ve doubled your chances.

Note that you will often get this same question but referring to playing cards (as in 3-Card Monte) or doors (as in Monte Hall/Let’s Make a Deal) instead of envelopes.

From here.

Signature

GdB

The light is on, but there is nobody at home.

 Profile

 Posted: 19 July 2012 12:54 AM [ Ignore ]   [ # 3 ]
Sr. Member
Total Posts:  5255
Joined  2007-08-31

A fellow had just been hired as the new CEO of a large high tech corporation. The CEO who was stepping down met with him privately and presented him with three numbered envelopes. “Open these if you run up against a problem you don’t think you can solve,” he said.

Well, things went along pretty smoothly, but six months later, sales took a downturn and he was really catching a lot of heat. About at his wit’s end, he remembered the envelopes. He went to his drawer and took out the first envelope. The message read, “Blame your predecessor.”

The new CEO called a press conference and tactfully laid the blame at the feet of the previous CEO. Satisfied with his comments, the press—and Wall Street - responded positively, sales began to pick up and the problem was soon behind him.

About a year later, the company was again experiencing a slight dip in sales, combined with serious product problems. Having learned from his previous experience, the CEO quickly opened the second envelope. The message read, “Reorganize.” This he did, and the company quickly rebounded.

After several consecutive profitable quarters, the company once again fell on difficult times. The CEO went to his office, closed the door and opened the third envelope.

The message said, “Prepare three envelopes.”

From here.

Signature

GdB

The light is on, but there is nobody at home.

 Profile

 Posted: 19 July 2012 06:32 AM [ Ignore ]   [ # 4 ]
Sr. Member
Total Posts:  9301
Joined  2006-08-29

Touché, GdB.  :-)

 Profile