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        riddles >> easy >> Tuition
        
(Message started by: alien2 on May 26^th, 2012, 12:13pm)

Title: Tuition
Post by alien2 on May 26^th, 2012, 12:13pm

Two youths are moonlighting, trying to earn money for tuition. They’re friends and they like riddles. While strolling and howling at the full moon, they suddenly find themselves in a strange room. There is an hourglass on the small round table and an electric bell on the wall. There are no windows or doors and the air is stale. A blurred figure appears, of little height and anthropomorphous: “My name is unintelligible to you. You can see me as I really am in your dreams. I have some supernatural powers. I like riddles too. If you solve one, I’ll give you the money for your college education. If not, I’ll make sure you never get it.

You see, I will take one of you to an adjacent twin room. This room has a button and graffiti, consisting of two separated different letters. If you push the button, and you’re allowed to push it only once, the bell will make a continuous buzzing noise. The letters could be A, B, C or D, and the one who remains in the 1st room must try to determine which are these letters. He can guess once and at his convenience. It is beyond your understanding how the rooms are illuminated and no sound whatsoever could pass through the walls.

Before this procedure begins, you are allowed an hour of time alone to discuss a plan. The time is up when the top bulb becomes empty.” The mysterious entity inverts the hourglass and disappears.

The youths enroll in college. What plan did they devise?

Title: Re: Tuition
Post by Grimbal on May 27^th, 2012, 2:12pm

I am probably overlooking something. As I understand it, the 1st person can go to the room and look at the letters, the second person can use the Eye of Providence to read that information from his friend's mind.

Title: Re: Tuition
Post by alien2 on May 28^th, 2012, 1:14am

I changed the riddle. I've excluded the Eye of Providence and added the bell. :-[

Title: Re: Tuition
Post by towr on May 28^th, 2012, 2:06am

[hide]Pick a song, so you can synchronize timing between the two of you fairly well. Pick 6 moments during the song (sufficiently far apart), which will signal the two letters chosen if the bell rings at/near that time. Simply press the button at the right moment and the other will know the two letters.[/hide]

Title: Re: Tuition
Post by ClairBear on May 31^st, 2012, 12:13pm

[hide]If I understand correctly, there are only 6 combinations of letters that could be written in the second room: AB, AC, AD, BC, BD, and CD. With that in mind, the two people assign a number to each of these combination: 0 for AB, 1 for AC, 2 for AD, etc. Then, when the person who is sent to the second room sees what the letter combination is, they can come up with the associated number to that combination.
Since it never says that the two people can't flip the hourglasses and their time is only up when the top bulb empties, it seems like they are allowed to flip the hourglass to use it to keep time. So every time that the hourglass is about to empty out, the two people will both flip their hourglass to keep time going, noting how many times they have flipped the glass.
When the person is sent into the second room, they will press the button when the number of times that they have flipped the hourglass matches up with the associated number to the correct combination of letters that he/she sees. To eliminate any confusion about how many times the hourglasses have been flipped, the person in the second room should press the button when the hourglass has approximately run-out half way[/hide]

Title: Re: Tuition
Post by towr on May 31^st, 2012, 1:02pm

But the puzzle only mentions one hourglass.

Title: Re: Tuition
Post by ClairBear on May 31^st, 2012, 1:28pm

It says that the second room is an "adjacent twin room". I took that to mean that the second room is identical to the first, except for the addition of the graffiti and the button.

Title: Keith Gilabert, "Tuition?"
Post by keithgilabert on Jun 4^th, 2012, 12:01pm

I think the first room is the same as the second...right?

very clever riddle.

Keith Gilabert

Title: Re: Tuition
Post by alien2 on Jun 7^th, 2012, 6:04pm

The rooms are identical, not what's in them.

Towr's idea is the right one, even though the expected answer is just a bit different.

Title: Re: Tuition
Post by Grimbal on Jun 15^th, 2012, 3:37pm

I assume that while the button is in one room, the bell can be heard in the other one...

They could make two pendula (pendulums) by dangling identical shoes at the end of equally long shoelaces. If the length is correctly adjusted, they could differentiate different times for a whole alphabet. If the transmitting person presses the button at a precise number of swings, different for each letter, and releases it later at a precise time, they could probably differentiate 2 letters among 26. For 4 letters, it is a piece of cake.

I like the idea that they would actually use a pendulum to read secret information from a sealed place.

Title: Re: Tuition
Post by Noke Lieu on Jun 21^st, 2012, 6:29pm

Just an aside- have you been watching Twin Peaks recently?
Two identical rooms, a (dancing) midget thazt you only get to meet in your dreams...

Title: Re: Tuition
Post by alien2 on Jun 22^nd, 2012, 2:22am

I watched Twin Peaks two decades ago. I was impressed by the serial drama.

Title: Re: Tuition
Post by 0.999... on Jun 22^nd, 2012, 9:04am

Measure respective heart rates using the hourglass. After separation, every ten minute interval will represent a pair of letters.

Title: Re: Tuition
Post by Grimbal on Jun 23^rd, 2012, 12:40am

The rooms are perfectly soundproof, but ... made of glass. They can see each other. Hell, even the graffiti is visible from the other room!

Title: Re: Tuition
Post by 0.999... on Jun 23^rd, 2012, 4:28am

Yes, and if the glass is tinted... well that table comes in handy.