Saturday, March 30, 2013
Persnickety Puzzling Puzzles….
For your weekend delectation….
A recent Jason Rosenhouse post offers some thought puzzles of a certain style here:
(here's the style: "If you ask me on Friday what day classes start, and I truthfully reply that they start two days after the day before the day after tomorrow, then on what day do classes start?")
;-) have at it!
And in the oldie-but-goodie brain-stretching department, it probably doesn't get any better than the classic "two envelope problem/paradox" (picking/switching between 2 envelopes of differing dollar amounts; one has n dollars, the other contains 2n dollars -- after you pick one and look inside, is it more advantageous to keep the chosen one or switch to the unchosen?) -- as is often the case, the precise, explicit statement or set-up of the problem is crucial in determining a solution (but even when the set-up is agreed-upon, debate ensues!). Most of you are probably somewhat familiar with the problem, but you can review it at Wikipedia here:
Keith Devlin gives his take here:
I especially like William Briggs' methodical analysis in 2 posts here:
And another interesting piece:
But it goes on and on and on…. a Google search produces copious material on this simple-to-state, insidiously-mind-bending problem:
(...don't blame me if your head explodes)