Just a little mock-up of a question I once had on an exam a very long time ago...thought you all might enjoy it. A coin collector lands on a desert island where there are only two denominations of coins: Nickels, who always tell the truth; and Dimes, who always tell lies. The coin collector comes across three coins, and asks the first coin what his denomination is, but can’t make out the mumbled answer. The second coin says, “He said he is a Nickel.” The third coin shouts at the second, “You liar!” Based on that exchange what can be inferred about the denominations of the three coins? And, of course...explain your answer.
Well either i am missing something or the first coin can not be inferred whether it is a dime or a nickel but the second is a nickel because if the first was a dime it would've said it was a nickel and if the first was a nickel it would've said it was a nickel so the second is telling he truth. The third is a dime because he is saying the nickel was lying which would be impossible so the third itself must be lieing making it a dime.
I really have to learn to scroll down and read the whole thread first. I just sat here and figured out how to explain it, scrolled down and there it was....DUH! Richard
Hmmm. I think I will wait until tonight when I have slippers on and a warm cup of tea in my hand.....
Whoops, I thought this thread was over, sorry. But of course you're right. No matter what denomination the 1st one is, he's always going to answer, "Nickel." But you'll be surprised how many people will agonize over this teaser for days even longer and still won't get it. Know why? It's because, when they hear the response was mumbled, they figure they can't figure out what it was, themselves,. So, they proceed to try to answer the question, without figuring that out. And you can't. Try it on some people, and you'll see. But you got it. Spock, now give him his prize.
I haven't read the other answers to this thread in an attempt to solve it myself...so if I repeat what was already said, I'm sorry. I see 2 possible endings for this story: In the first scenario, you assume that the third coin is telling the truth (stating that the coin who proclaimed "He's said he's a nickel" is in fact a lair). In that case, the third coin is a nickel (who tells the truth), the second coin is a dime (who lie's) and the first coin is also a dime (because it is untrue that he's a nickel). So, to recap: First Coin: Dime Second Coin: Dime Third Coin: Nickel In the second scenario, you assume that the third coin is lying when he says to the second coin "you liar." Therefore, the third coin is a dime. If the statement "you liar" is itself a lie, then the second coin is telling the truth when he's says "he said he's a nickel" If the second is telling the truth he, like the first coin, is a nickel. So, to recap: First Coin: Nickel Second Coin: Nickel Third Coin: Dime I'm unsure if this can be solved any further.
LOL! Richie, if the 1st one is a Nickel, who always tells the truth, he's going to tell the truth and answer he's a Nickel. If the 1st one is a Dime, who always tell lies, he's going to lie and answer he's a Nickel. In both cases, no matter what denomination the coin is, he's going to answer he's a Nickel. Therefore, you don't know what denomination the 1st coin is, but you know what his mumbled answer was--it was, he's a Nickel. Go from there to the respective statements, and you know the denominations of the other two coins. I've had people going for weeks on this one, so don't feel bad. In fact, try it on some of your co-workers, you'll have a blast listening to some of their answers.
Dang I must be better then I thought and im a YN And btw if you want to try your hand at more of these brain teasers get the boook Lady or the tiger.
