X implies Y I really couldnt understand Part I as the question seemed irrelevant. How could a white triangle be frobby because it has both shape and color? And since you're thinking on 'a' shape and color, there are no more items to ponder over their 'frobbiness' Part II The minimum number of cards to flip over are 2 in order to prove the rule is true. Those two cards will be: 5 and F The rule says that a card with an odd number MUST have a vowel on the other side and says nothing of the other way round. As a result we dont need to flip the E card as the other side need not be a vowel. We need to flip 5 since its an odd number and the other side needs to be a vowel. We need to flip F to ensure that the other side is NOT an odd number therby verifying the rule Hadi Mohammed Thursday, August 07, 2003 I'm notoriously bad at puzzles, but I'm gonna give these a go anyway. Part I All except one will always be frobbies, won't they? The black circle is the total opposite of the white triangle, so it's not the frobby, and all the other ones are. Answer: yes Part II You don't have to flip the 2 card because it doesn't matter what's on the other side. You have to flip the 5 card to make sure it has a vowel on the other side. You have to flip the F card to make sure there's NOT an odd number on the other side. You don't have to flip the E card because if there's an odd number on the other side, the rule is satisfird. If there's an even number on the other side, well, the rule doesn't care about that. Answer: 2 henning henning Friday, August 08, 2003 Part I   Since white triangle is frobby, then the we can assume that either white or triangle is one of the characteristics "in the interviewer's head," but not both.  That implies that either black or circle is the other characteristic.    In that case, you can say that the black circle is also frobby.  It must have one and only one of the characteristics, for if it had both then the white triangle would have none and thus not be frobby.   That leaves the black triangle and the white circle.  One has both traits, the other none.  It doesn't matter which is which because both are not frobby.   Therefore to answer the question, yes, I can tell you the frobbiness of the other items:   white triangle...frobby   white circle...not frobby   black triangle...not frobby   black circle...frobby Part II   The other responders have this correct.  Both the 5 and F need to flipped.  The 5 must have a vowel and the F must not have an odd number. Sergio Loscialo Wednesday, August 27, 2003   Fog Creek Home