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        riddles >> what happened >> 2005 and 1975
        
(Message started by: Roy on Jul 24^th, 2006, 3:43pm)

Title: 2005 and 1975
Post by Roy on Jul 24^th, 2006, 3:43pm

John is on a raft, adrift in the ocean with several other survivors of a shipwreck. The others are too weak, so he or Mike will swim to a nearby island to look for help. It is almost certainly suicidal, due to the circling sharks, but they have little else to hope for. Mike takes the lose change from his pocket and puts two pennies in a hat. He tells John that one is a 2005 penny, and the other 1975. If John picks the newer penny he can stay on the raft, and Mike will risk his life. If John picks the older penny, he must go. John has seen that both pennies were actually dated 1975, but he doesn't want to say anything, because Mike is a big guy. How does he win, and get Mike to go, without exposing him as a fraud in front of the others?

Title: Re: 2005 and 1975
Post by cchris on Jul 24^th, 2006, 4:27pm

Take a penny from his pocket?

Title: Re: 2005 and 1975
Post by Roy on Jul 24^th, 2006, 4:58pm

who, John? no, there's only the two 1975 pennies.

Title: Re: 2005 and 1975
Post by graphia on Jul 24^th, 2006, 5:08pm

Propose that they flip the coin instead? I really have no idea.

Title: Re: 2005 and 1975
Post by Icarus on Jul 24^th, 2006, 6:47pm

Fortunately, one of the other passengers was a maiden who had escaped marriage to an evil mayor. She had told him how she had gotten out of the marriage, so he knew just what to do.

Title: Re: 2005 and 1975
Post by Roy on Jul 24^th, 2006, 10:39pm

Icarus: Which was that variation?

No, no coin flips.

Title: Re: 2005 and 1975
Post by BNC on Jul 24^th, 2006, 11:29pm

on 07/24/06 at 22:39:14, Roy wrote:

Icarus: Which was that variation?

See in the main page (easy): evil mayor.

Title: Re: 2005 and 1975
Post by Puffster on Jul 25^th, 2006, 12:12am

Couldn't [hide]John pick a penny from the hat, hold it in his hand (or drop it somewhere) and then show everyone that the remaining penny in the hat is a 1975 penny. Therefore, everyone would assume that John picked the (nonexistent) 2005 penny and Mike would have to go.[/hide]

Title: Re: 2005 and 1975
Post by graphia on Jul 25^th, 2006, 1:25am

There's one or two conditions that make this puzzle different from the mayor one, namely [hide]in the mayor puzzle the mayor can't look like the bad guy or he'll be deposed; in this puzzle there's only John and Mike that can actually do anything as everyone else is too weak. In fact, since Mike already knows that the pennies are rigged there's nothing John can do except have everyone else know that he was morally right before he dies (not much comfort), as there is no authority over Mike's actions. I'm not entirely sure why he'd agree to the bet in the first place if he knew for certain it was rigged but hey, who's complaining?[/hide]

The only answer I can justify is [hide]that John is royally screwed[/hide], but I believe that the intended answer is as Puffster said, [hide]John should drop the penny he picks over the side of the raft[/hide].

Title: Re: 2005 and 1975
Post by Roy on Jul 25^th, 2006, 3:55am

Basically, yes.[hide] Mike picked either of the coins and quickly slipped up and the penny went over into the water with one of the coins still in the hat reading1975,[/hide] everyone else(they're weak, not passed out) can see he pickedthe '2005' coin. Thus, if John says anything suspicious about Mike cheating his trick is null and void.