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        riddles >> easy >> Tempus fugit, riddles and beyond
        
(Message started by: alien2 on Nov 16^th, 2023, 5:42am)

Title: Tempus fugit, riddles and beyond
Post by alien2 on Nov 16^th, 2023, 5:42am

1. I can tell You the exact number of the stars in cosmos. But how?

2. I know beyond a shadow of a doubt the exact number of the stars in cosmos. Can You explain it?

3. You wake up in a well illuminated room. You have no idea how You got there. You notice that there are no openings of any kind. At least, quantum teleportation comes to mind. There are 99 ticking analogue clocks on the four walls, showing one o’clock at the time, either AM or PM, you’re not sure, and one analogue ticking clock that shows five o’clock. Suddenly, you hear a deep voice: “Welcome to your worst nightmare. It is afternoon. Either 99 clocks show the wrong time and one clock shows the correct time, or 99 clock show the correct time and one clock shows the wrong time. In order to get out of this room, free as a bird, you must assert the claim as to which clocks show the wrong time.” What would You say?

4. There is a basic flat bridge w/o fence, 40 meters long and 4 meters wide, out of wooden boards, each 4 meters long (as wide as the bridge and placed accordingly) and a meter wide, perfectly symmetrical, bridging a calm river below. As you’re crossing the bridge, to get to the other side like the chicken (just the joke), by approaching the end of the bridge, you notice a gap 4 meters and 3 centimeters long (since a few boards were not perfectly symmetrically placed during construction, but at least they are still all parallel to each other like horizontal lines). That is to say, 4 wooden boards fell into the river, because the bridge is rather old. Still, what remains of the bridge at least appears to be sturdy enough and very symmetrical. However, as you start to return to the beginning of the bridge, you notice one loose wooden board behind you. There are no other objects at your disposal that you could use. Is there a way to get to the other side?

5. A man asserts the claim to fellow riddlers: “There are no stars in the universe.” He was telling the truth. But how?

Title: Re: Tempus fugit, riddles and beyond
Post by jollytall on Nov 16^th, 2023, 8:06am

1, 2: cosmos is just a word and there is no star in it, unlike e.g the famous university: C*mbridge.
3. The 99 ticking clocks are analogue, and you cannot know if that is AM or PM. The single one is also ticking, but probably not classic analogue, but a digital display one with mechanical mechanics, showing a 24 hour day. Since it shows 5 o'clock (not 17), and we know that it is afternoon, only the 99 clocks can show the correct time.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Nov 16^th, 2023, 10:49am

on 11/16/23 at 08:06:10, jollytall wrote:

1, 2: cosmos is just a word and there is no star in it, unlike e.g the famous university: C*mbridge.

Yes! As per an alternative answer, and a well-known one, just say: "You just did."

on 11/16/23 at 08:06:10, jollytall wrote:

3. The 99 ticking clocks are analogue, and you cannot know if that is AM or PM. The single one is also ticking, but probably not classic analogue, but a digital display one with mechanical mechanics, showing a 24 hour day. Since it shows 5 o'clock (not 17), and we know that it is afternoon, only the 99 clocks can show the correct time.

An interesting point of view. However, all clocks are analogue, regarding the expected answer.

Thanks for playing! Just play again.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Nov 16^th, 2023, 10:53am

However, as per the 2nd riddle, there is a valid answer, I think, regarding the actual number of the stars in cosmos; so no tricks, just as it states, this man, apparently guilty of something, can actually provide the exact number of the stars in cosmos. (There is, of course, a catch, but at least there's no pun.) I only hope that wording of the riddle agrees with the expected answer.

Title: Re: Tempus fugit, riddles and beyond
Post by rmsgrey on Nov 17^th, 2023, 9:52am

I'm no bartender, but I believe the recipe for a cosmo doesn't include any stars.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Nov 17^th, 2023, 12:19pm

Nope. No pun intended. Cosmos happens to be cosmos. Nice try.

Title: Re: Tempus fugit, riddles and beyond
Post by rmsgrey on Nov 30^th, 2023, 7:48am

For 3, does one's assertion have to be correct?

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Nov 30^th, 2023, 10:14am

on 11/30/23 at 07:48:00, rmsgrey wrote:

For 3, does one's assertion have to be correct?

Yes. Undoubtedly.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Dec 16^th, 2023, 8:44am

2. SPOLIER: [Hide]One cannot tell the exact number of stars in the present. Perhaps another timeline resolves the dilemma.[/hide]

3. Clue: [Hide]This site is awesome! William must be proud of his HANDIWORK.[/hide]

Title: Re: Tempus fugit, riddles and beyond
Post by rmsgrey on Dec 19^th, 2023, 9:43am

For 3, if we know that the correct time is one of two possibilities, that leaves 718 other possibilities (if accurate to the minute) that we know are definitely wrong.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Dec 19^th, 2023, 11:10am

Interesting stuff.

You might be overthinking it,though. The expected answer is a bit shallow. There's a catch.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Dec 21^st, 2023, 2:31pm

A 4th riddle was recently added.

Title: Re: Tempus fugit, riddles and beyond
Post by jollytall on Dec 22^nd, 2023, 1:15am

It is not said how wide the bridge is. So I assume it is 10m wide and so falling 8 pieces (1m wide each) into the river and still leave the bridge symmetrical and I can still walk on either of the two planks on one of the sides of the gap in the middle.
And, yes, I do not touch the loose one, hoping that those chase me will try to use that and fall into the river.

But if the bridge is only 8 meters wide, i.e. all the boards of one section fell in, I can still use the 4x1m loose board, since its diameter is 4m 12.3 centimeter and that is enough to bridge a 4m 3cm gap. It is a bit shaky, but with good balancing doable.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Dec 22^nd, 2023, 4:29am

I revised the riddle accordingly. Hope it looks clearer now.

I believe You solved the riddle, which looks impossible only at 1st glance, only to realize it is a walk in the park, so to speak, or it would be if there were no danger. And yet, I'm not sure I follow entirely, since math is not my forte. Perhaps you can simplify your answer and elaborate a bit, just so there is no confusion.

Still, aiming for the 2nd solution as well, let us assume that the gap is more than 4 m and 3 cm long, say, 4,5 m long. I wonder if then there is a way to get to the other side. And yes, I believe there is.

Title: Re: Tempus fugit, riddles and beyond
Post by jollytall on Dec 22^nd, 2023, 6:36am

OK, so in the original version, the bridge was 40 m long and unknown wide. It was covered with 4x1m planks. You also said a 4 m (+ a bit) gap and 8 missing planks.
For the first solution, I said that the planks are in the direction of the bridge itself (as it was not specified then), i.e. the bridge had 10 pieces of 4 m long planks after each other. Since 8 pieces fell into the river, the bridge had to be at least 8m wide, otherwise the gap had to be longer (or the boards are used in more than one layer on top of each other). But if the bridge was even more than 8 m wide (again it was not specified, so I can assume a 10m wide bridge), then the 8 missing planks does not cause a problem, because I can walk across just passing the hole (4x8m) in the middle.
My second solution did not use this trick. If simply the gap is 4m long and as wide as the bridge itself, then we need to cover the gap somehow. Basic Pythagoras tells us that a 4x1m board if placed a bit rotated can cover 4m13cm, what was enough in the first solution.

Now, after the clarification, it is more confusing. If the planks are perpendicular to the bridge and the width of the bridge is the length of the plank, then one missing plank makes a 1 m long gap (with full width). If 8 planks fell into the water and they are all neighboring, then the gap is 8 m, not 4 and a bit. So, I do not even understand the question.

Still, yet another non-conventional solution:
The fact that the top layer covering boards are missing, you say nothing of the underlying structure. You can walk, climb through the structure itself not even using the loose board, but if you use that and move it step-by-step somehow, it is even easier and safer.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Dec 22^nd, 2023, 9:01am

Yes, tilt the board.

I corrected the riddle. I hope it looks better now. In my defense, I've dyslexia etc. I can't apologize enough.

The 2nd solution is still out there.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Dec 24^th, 2023, 7:00pm

A 5th riddle was added recently.

Title: Re: Tempus fugit, riddles and beyond
Post by alien2 on Dec 25^th, 2023, 10:32am

Merry Christmas!

And for 3, yes, you can [Hide]play with[/hide] watches.