There is an accounting firm that has been using puzzles of various types in their ads. Today on the train into work, I saw one of their ads, with a logic puzzle. I am posting the puzzle here and inviting readers to comment with their solutions and reasoning behind the solution. Comments will be screened until at least Wednesday (and maybe as long as Friday).
The Puzzle:
Three supermodels are invited into a swanky and exclusive Fifth Avenue shop. They are shown a shelf upon which are five pashminas  three in deep cerulean and two in saffron. All three are then blindfolded, and one pashmina is draped over each. The remaining two pashminas are returned to the shelf. The models are lined up so that none of them can see the shelf.
The third supermodel's blindfold is removed, and she is asked whether she can tell, by looking only at the other two supermodels, what color pashmina she is wearing. She replies that she cannot.
The second supermodel's blindfold is removed, and she is asked whether she can tell, by looking only at the first supermodel (and, obviously, having heard the third supermodel's reply), what color pashmina she is wearing. She, too, replies that she cannot.
The first supermodel, before her blindfold can be removed, says "I am wearing a ___________ pashmina  may I keep it?".
What color pashmina was the first supermodel wearing, and how do you know?
Page Summary
hrrunka :: (no subject) [+2] unixronin :: (no subject) [+1] :: 1st pashmina glenbarnett :: (no subject) [+1]
Links
Traveller Sites
Favorite Webcomics
Online Games
Society for Creative Anachronism
January 2017

Logic Puzzle Advertising
The Answer
The first supermodel was wearing a deep cerulean pashmina. The third supermodel sees two other models wearing blue pashminas. Either they are both wearing blue ones, or one is wearing blue and the other one saffron. Either way, she doesn't have enough information to know whether she is wearing the remaining blue one or the remaining saffron one. The first supermodel is a ringer. Here's my reasoning, which is probably wrong. First is wearing a deep cerulean one. Ah. Missed that bit. Or forgot it when I was writing out the explanation. Accounts for the subsequent uncertainty I was feeling. If SM1 and SM2 are wearing safron then SM3 would know that she is wearing celurean. But this is not the case, Are you sure that's all the information? It does not appear solvable given the provided information. If #3 saw red scarves on both #1 and #2, she would know the remaining 3 (including her own) are blue. Since she can't tell the color of her own scarf, at least one of #1 and #2 has a blue scarf. If model 1 and 2 both bore saffron, then model 3 would know that hers could only be cerulean, as all the saffron would be accounted for. The first supermodel is wearing a cerulean pashmina. Well, three supermodels, two colors of pashminas (pashminae?). Eight possibilities. So, let's just elaborate the possibilities:
Well, no, there are only seven possibilities. Possibility #0 isn't valid, because all three supermodels are wearing saffron pashminas, but there are only two saffron pashminas to go around. So, let's look at possibility 1. Supermodel three looks at supermodels one and two, sees that both saffron pashminas are accounted for, knows she must be wearing a cerulean one, and would answer "yes" to her question. However, the problem states she answered "no", so the answer can't be possibility 1. Since supermodel three said "no", supermodel two knows that she and supermodel one are together wearing at most one of the two saffron pashminas: either supermodel two is wearing one, or supermodel one is wearing one, or neither supermodel are. So, in possibilities 2 and 3, supermodel two looks at supermodel one, sees a saffron pashmina, knows she must be wearing a cerulean one, and would answer "yes" to her question. However, the problem states she answered "no", so the answer can't be possibilities 2 or 3. In all remaining possibilities (4 through 7), supermodel three looked at supermodels one and two, saw at most one saffron pashmina, so answered "no". Also, supermodel two looked at supermodel one, did not see a saffron pashmina, could not tell what color pashmina she was wearing, so answered "no". However, in all remaining possibilities (4 through 7), supermodel one was wearing a cerulean pashmina. So, that is what she must have been wearing. QED. (Anonymous)
1st pashmina
1st pashmina is cerulean. Because in order for 3rd to say she doesn't know then at lease ONE of the 1st two must be cerulean  because if the 1st two were saffron then since there are only two saffron then 3rd supermodel would know she herself is wearing cerulean. Now only way 2nd supermodel could know her own color is if 1st supermodel is saffron (in which case, based on 3rd model's reply she would know her own must be blue). But 2nd model also doesn't know, therfore only possibility is that 1st is wearing cerulean. A variant of the old Three Hats (or Three Philosophers) puzzle (though somewhat different from the also well known "Hat problem"). 