If you would like to see the solution to my previous puzzle, please see that blog. I posted a solution.

Puzzle #2

Consider seven identical marbles. They are supposed to all weigh the same amount, but one is very slightly heavier. We have a very sensitive balance that is adequate for this puzzle. Find the heavy marble.

We could test them two at a time and in at most three tests we would know the heavy marble. Either we would find it directly in one of the three tests or it is the one left over.

Devise a test procedure that finds the heavy marble in an at most number of tests that is less than three.

RMac

If you would like to see the solution to my previous puzzle, please see that blog. I posted a solution.

Puzzle #2

Consider seven identical marbles. They are supposed to all weigh the same amount, but one is very slightly heavier. We have a very sensitive balance that is adequate for this puzzle. Find the heavy marble.

We could test them two at a time and in at most three tests we would know the heavy marble. Either we would find it directly in one of the three tests or it is the one left over.

Devise a test procedure that finds the heavy marble in an at most number of tests that is less than three.

RMac

It is a trick with words.  If he had given the dollar back to them they would have paid 26 dollars.  Since he in effect stole it from them they paid a dollar more or 27 dollars.  It is the extra dollar they paid don’t count it twice 

RMac 

Quoting Dakota35: Here's one that was always strange to me, I'm sure plenty have heard it before.  3 guys walk into a motel looking for a room.  The guy at the front desk says the cost of a room is $30.  So each guy pulls $10 out of his wallet to pay for the room.  Later, the guy at the front desk remembers that there was a discount room special that week and the room was only $26.  Being a honest man, he removes $4 from the register and heads to the men's room to give them their money.  On the way, he starts thinking how he is going to divide $4 amoung 3 men.  So he decides that he'll just give each $1 and keep $1 for himself.  So he does exactly that, he gives each man $1 and keeps $1 for himself.  Now that makes it so each man paid $9.  3 men x $9 = $27 + $1 man put in his pocket = $28.  But the room only cost $26???

Curious – you need to drink your coffee quick or the solution will be posted before you get around to it.  Thanks for posting. 

RMac
 

Quoting Curious2078: Now this I can't do without a lot more coffee than I have at hand now.  But, somehow, I think I SHOULD be able to do it 3 minutes.   I'll be very anxious to see the answer.

DONTFITMOLD – You started off on the right track.  See Dakota’s solution.  Nice joke.  Thanks for posting.

Optimist – we only have seven marbles?  So I am a bit puzzled by your solution.  Thanks for posting.

Liv – One or two puzzles does not disqualify you.  Thanks for posting. 

RMac

DONTFITMOLD – You started off on the right track.  See Dakota’s solution.  Nice joke.  Thanks for posting.

Optimist – we only have seven marbles?  So I am a bit puzzled by your solution.  Thanks for posting.

Liv – One or two puzzles does not disqualify you.  Thanks for posting. 

RMac

Dakota – I hope you do not think I said you were a member of Mensa.  I used “may” in the sense of “might be” because I do not know either way.

Your solution is correct.

No need for me to post one.

RMac
 

Quoting Dakota35:  Okay, so we have 7 marbles.  Divide the marbles into 3 groups.  3,3,1.  I assume we are talking about a balance type scale where weight is shown to be equal on both sides?  So place 3 marbles on each side.  If the weight is equal then we know that the single marble that was not weighted is the heavier.  If ones side of the scale is heaver then we know it must be within those the 3 marbles.  So now take those three marbles and remove 2 and weight.  If the weight is equal then we know it must be the one we didn't weight, if the weigh is different then we know which one it is? Next time you meet a smart Hispanic, be sure and tell them they must be a Mesa member....see how they respond. :)

A bartender is sitting behind the bar on a typical day, when the door bursts open and in come four exuberant blondes. They come up to th bar, order five bottles of champagne and ten glasses, take their order over and sit down at a large table. The corks are popped, the glasses are filled and they begin toasting and chanting, "51 days, 51 days, 51 days!" Soon, three more blondes arrive, take up their drinks and the chanting grows. "51 days, 51 days, 51 days!" Two more blondes show up and soon their voices are joined in raising the roof. "51 days, 51 days, 51 days!" Finally, the tenth blonde comes in with a picture under her arm. She walks over to the table, sets the picture in the middle and the table erupts. Up jumps the others, they begin dancing around the table, exchanging high-fives, all the while chanting "51 days, 51 days, 51 days!" The bartender can't contain his curiosity any longer, so he walks over to the table. There in the center is a beautifully framed child's puzzle of the Cookie Monster. When the frenzy dies down a little bit, the bartender asks one of the blondes, "What's all the chanting and celebration about?


The blonde who brought in the picture pipes in, "Everyone thinks that blondes are dumb and they make fun of us. So, we decided to set the record straight. Ten of us got together, bought that puzzle and put it together. . .the side of the box said 2-4 years, but we put it together in 51 days ! "

A bartender is sitting behind the bar on a typical day, when the door bursts open and in come four exuberant blondes. They come up to th bar, order five bottles of champagne and ten glasses, take their order over and sit down at a large table. The corks are popped, the glasses are filled and they begin toasting and chanting, "51 days, 51 days, 51 days!" Soon, three more blondes arrive, take up their drinks and the chanting grows. "51 days, 51 days, 51 days!" Two more blondes show up and soon their voices are joined in raising the roof. "51 days, 51 days, 51 days!" Finally, the tenth blonde comes in with a picture under her arm. She walks over to the table, sets the picture in the middle and the table erupts. Up jumps the others, they begin dancing around the table, exchanging high-fives, all the while chanting "51 days, 51 days, 51 days!" The bartender can't contain his curiosity any longer, so he walks over to the table. There in the center is a beautifully framed child's puzzle of the Cookie Monster. When the frenzy dies down a little bit, the bartender asks one of the blondes, "What's all the chanting and celebration about?


The blonde who brought in the picture pipes in, "Everyone thinks that blondes are dumb and they make fun of us. So, we decided to set the record straight. Ten of us got together, bought that puzzle and put it together. . .the side of the box said 2-4 years, but we put it together in 51 days ! "

Diana -- Dakota solved the last one.  He may be a member of Mensa, but the solution does not require that.  It only required using the facts that you already know.  The first part was easy.  The second part required a bit of bookkeeping.  Anyhow, we shall see if anyone solves this one.  I’ll post the solution either way.   

The Mensa tests are sometimes posted on the internet.  I used to play with them sometimes.  Their puzzles are way harder than these.   

I don’t smoke or play the lottery, but alas, I don’t have a Ferrari.  I have been known to have an occasional beer.  Definitely not 3 six packs a day, more like one beer a week, at most.   Still I don’t have a Ferrari.

Guess I must have been spending all that money I saved on other stuff.

RMac   

Quoting Diana3316: Hmmm.....well RMac....we used to have two Mensa members on here....but now only one....and I don't think any of the rest of us will be able to solve your puzzles.  :))