I owe it to the Den to post at least one of these without error.
Possibly this one does that.
Give the longest route (sequence of city numbers) that visits all the cities
(a) not returning to starting city (sum of 7 distances - starting point matters)
(b) returning to starting city (sum of 8 distances - starting point does not matter)
This puzzle has more choices than the first one.
Cities lie clockwise on the perimeter of a 6x6 square:
6--O------O-------+--------O
|3 4 5|
| |
| |
4--+ +
| |
| |
| |
2--O2 6O
| |
| |
|1 8 7|
0--O-------+-------O-------O
| | | |
0 2 4 6
+----+---+---+
|City| x | y | Distances:
+----+---+---+ 8.485 1-5 3-7
| 1 | 0 | 0 | 7.211 2-5 3-6 3-8 4-7
| 2 | 0 | 2 | 6.325 1-4 1-6 2-7 4-8 5-8
| 3 | 0 | 6 | 6.000 1-3 1-7 2-6 3-5 5-7
| 4 | 2 | 6 | 5.656 4-6
| 5 | 6 | 6 | 4.472 2-4 2-8
| 6 | 6 | 2 | 4.000 1-8 2-3 4-5 5-6
| 7 | 6 | 0 | 2.828 6-8
| 8 | 4 | 0 | 2.000 1-2 3-4 6-7 7-8
+----+---+---+
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#332193 Driving man's delight - 2 a harder puzzle
Posted by bonanova
on 15 May 2013 - 08:16 PM
#331745 Which liar done it?
Posted by bonanova
on 07 May 2013 - 09:21 AM
Sergeant McGuffy remarked to his lieutenant one day after it was all over. "The way I reconstruct the crime, the innocent people were so excited when they first talked to us, they each got one fact wrong. But, the killer wanted to confuse our trail - and so coolly lied from beginning to end." Let's recap what we know ...
Egmont VanDorn has been found dead in his apartment. From the beginning, it is pretty clear to the police that this was no accident. Before they can be separated, the four young people who found the body - Arnold, Betsy, Charles and Daisy - eagerly begin to tell their story.
- "If, as the police say, Egmont was injured between four and five," said Daisy, "that must let us all out. We were all together having dinner for at least two hours before we came over here."
- "But we all arrived at seven," Charles pointed out.
- "Arnold said that it was six o'clock at the time, just before we opened the door. Didn't you Arnold?" said Daisy.
- "I said it was just seven on the nose," said Arnold. "Sorry, honey."
- "I have no idea what he said or what time we got here," declared Betsy. "The thing I remember is the gas in the hall. We rang the doorbell, and no one came and no one came, and then I smelled the gas. My heart turned over, I thought to myself, he's dead. I just know he's dead."
- "Don't dramatize yourself," said Daisy coolly. "There is no way that you could have smelled the gas before we opened the door. The place was locked up, and sealed too, tighter than a drum. We'd still be in the hall if Eggy hadn't given me a key last week."
- "There was gas in the hall, all right," said Charles. "I smelled it before we opened the door. You seemed to take forever getting your key out. When you finally got the door opened, the gas just streamed out."
- "That was a pretty dangerous thing you did, Charles," said Arnold, "turning on the lights the way you did. Didn't it occur to you that a spark at the light switch could have blown us all up."
- "The lights were already on, Arnold," Charles replied.
- "For my part, I'm sorry about pulling him out of the oven - tampering with the evidence and all that," said Arnold. "Murder never crossed my mind. Locked room, you know. All I could think of was that maybe he was alive and we could still save him."
- "I don't believe this," said Daisy. "You didn't pull him out of the oven. I did. You ran and opened the window. Very good move, too, I thought at the time."
- "I opened the window!" cried Betsy. "I was dizzy from the fumes, and I knew I needed to do something fast."
- "The only things you opened were the door to the liquor cabinet and a bottle of Scotch, Betsy." Charles laughed at her. "And I thought they were good moves."
- "That was Arnold who got out the Scotch," said Betsy. "Don't you remember our sitting there after you called the police, and Arnold passing out the glasses?"
- "It couldn't have been me. Must have been you," said Arnold. "I've never been here before, I didn't even know where he kept the stuff. Charles, what did you do?"
- "Do you know what? I don't think I did anything. I remember quite clearly, walking over here with you after that long dinner we had together, and then seeing poor Eggy's feet through the door. But after that, I don't think I did a thing, except stand there gasping."
OK it's time to make an arrest.
Which liar done it?
- 1
#330616 Alhazen's problem expanded
Posted by bonanova
on 14 April 2013 - 07:14 AM
In the plane the basic Alhazen's problem can be stated three ways: It is by no means a simple problem, and extending it to the sphere seems more like a research project than a brain teaser. I looked at it for a few minutes to see whether the great circles involved in the extended problem could be brought in a single projection to the plane in a way that they all became lines. I convinced myself that they can't. Not to leave the question without some reward for the minor research, however, I refer the interested puzzler to this simulation of the Billiards problem. Happy shooting. Hint: press the space bar. Edit: A circular table might screw up your billiards game, but it does have the advantage of taking less space from your man cave.
find an isosceles triangle whose legs pass through two given points.
find the point on a (concave) spherical mirror where light incident from a source will reach an observer.
find the point on a circular billiards table to stroke a ball so that on one carom it will hit an object ball.
- -1
#330425 Balancer's Chess
Posted by bonanova
on 07 April 2013 - 07:03 PM
What if there were no diagonals?
. - - - - - - .
- . - - R - . -
N - . - - . B P
- - - . . Q - -
- - - . . - - -
- - . - - . - -
- . K - - - . -
. - - - - - - .
- 1
#329821 Number game 1
Posted by bonanova
on 19 March 2013 - 10:44 AM
1 2 3 4 5 6 7 8 9
Arrange these numbers into two separate groups so that they add up to same total.
Note : you cant turn 9 upside down and make it 6
Spoiler for Looks likeYou have to turn the 9 into a six.
Numbers 1-9 total 45, which can't be evenly split.
Making the 9 a 6 reduces that total by 3 to 42.
So we need two groups that each total 21.
1 2 3 4 5 6 and 6 7 8 should do it.
Or turn the 6 into 9, increasing the total by 3 to 48.
1 2 3 4 5 9 and 7 8 9 do it for that case.
this is what even i think how can you split 45 into two equal parts...P.S- he noted that we cant use 9 as 6...
Ah, I misread that. Good catch.
He did not say that you could not turn the 6 into a 9.
- 1
#329652 Complete the Series 2
Posted by bonanova
on 14 March 2013 - 04:31 PM
Spoiler for31 and 10000Spoiler for explanationNumber 16 represented in base 16-n, for n in 1..14
Good solve ... although I got the "basic" nature of the puzzle, I did not see the second "?" in the OP.
- 1
#329547 How many tickets?
Posted by bonanova
on 12 March 2013 - 12:39 AM
Suppose n tickets numbered 1-n are in a box, and you draw one of them
You don't know how many tickets are in the box, but you are asked to estimate how many there are.
Your ticket has the number p on it.
What estimate of n has the highest likelihood of being correct?
It seems like this problem is dependent upon what is a reasonable a priori distribution for N.Spoiler for
Let P(N) be the prior distribution for the number N. Let P(p|N) be the conditional probability for p given N; we know that P(p|N) = 1/N. We wish to compute the conditional probability P(N|p), which can be expanded using Bayes theorembayesian.png
So, if we are given a well-defined probability function P(N), we can easily compute the number N that gives that maximum probability P(N|p).
The problem is that we are not given what P(N) is. One reasonable choice would be to assume that P(N) is the improper uniform distribution from p to infinity (every number has an equal chance of occuring). However, if we plug that improper distribution into the equation above, we would be able to cancel out P(N), but we'd end up with a harmonic series in the denominator, which does not converge.
Oh wait, the answer is much simpler than that. Turns out this is the easiest bonanova puzzle I have ever seen =)Spoiler for
Since "n tickets numbered 1-n are in a box", if we get number p = (1-n), then it is easy to see that n = 1 - p.
LOL
That may be the first and only time I use LOL in this forum.
I'm not that clever. Really.
But I love it. It's a better puzzle than the one I intended.
Honorable mention.
.
- 1
#329440 Give a monkey enough rope
Posted by bonanova
on 09 March 2013 - 02:32 AM
Конечно ...Spoiler for is Russian translation available?If "...the weight of the weight and the weight of the rope were together half as much again as the weight of the monkey," how can that system be in equilibrium?Веревка подбежал шкив, на одном конце была обезьяна, на другом конце вес.Два оставшихся в равновесии.Вес каната было 4 унции / футбол, а в возрасте от обезьяны и мать обезьяны составил четыре года.Вес обезьяна была много фунтов, как мать обезьяны было лет, и весом весом и весом каната вместе были в полтора раза больше, поскольку вес обезьян.
Вес вес превышал вес веревки, как многие фунтов, как обезьяна лет, когда мать обезьяны был вдвое старше брата обезьяны было, когда мать обезьяны был вдвое старше брата обезьяна будет, когда брат обезьяны в три раза стара, как мать обезьяны Когда мама была обезьяна была в три раза стара, как обезьяна в пункте 1.
Мать обезьяны был вдвое старше обезьяна Когда мать обезьяны был наполовину стара, как обезьяна будет Когда обезьяна в три раза стара, как мать обезьяны было, когда мать обезьяны в три раза стара, как обезьяна в пункте 1.
Возраст матери обезьяны превысил возраст брата обезьяны на такую же сумму, как возраст брата обезьяны превысил возраст обезьяны.
Какова была длина веревки?![]()
![]()
So the rope has legs and plays footbal?! And monkey's mother is a male?! And age is money?!Was it Google translation? I guess, it'll be awhile before computers can understand and translate natural language.Although it's worth noting that about the only bit translated correctly, is that very thing, which I misunderstood. The translation states, the weight of the rope together with the weight is 1.5 times the weight of the monkey, as the problem statement intended. Whereas I understood it as half weight of the monkey.
I was going to add the caveat that I cannot verify the usefulness of google translate. But yes, I thought all monkeys played football.
- 1
#329405 4 x 4 cards
Posted by bonanova
on 08 March 2013 - 09:59 AM
Spoiler for what about thisAS QC JH KD
JD KS AC QH
KC JS QD AH
QH AD KS JCIN SECOND ROW SECOND COLUMN IT SHOULD BE 'KH'. I TRIED TO EDIT THE POST BUT EDITING FAILED.
Hint: To edit after time elapses, copy / edit / paste onto a new post. ![]()
- 1
#329101 Give a monkey enough rope
Posted by bonanova
on 26 February 2013 - 10:10 AM
- -1
#328901 Stopping and Turning back hands of time
Posted by bonanova
on 21 February 2013 - 11:36 PM
Here's what I think. Disturbing. A small number of cycles no longer gets us to a reading of 12:00:00. Look at the first case, it's easier. 288n = 1716m is true when n=1716 and m=288. The total elapsed time would be 12m + 2n = 6886 hours or just short of 287 days.
A normal clock has eleven times between midnight and noon when H and M coincide, counting only midnight or noon. They are equally spaced, and occur 12/11 hours apart. If this were a normal clock, we should add 1-hour waits at each of these and come up with 12+11 = 23 hours for the total elapsed time.
But if we start the clock, so to speak, with the hands leaving midnight, and we stop it with the hands reaching noon, then we should exclude them both and add only ten 1-hour waits, for a total elapsed time of 22 hours.
Both these answers are wrong. We don't have a normal clock.
When H commences motion at the 12/11 point [when the clock reads 1:05:27], M is moving backward. They next coincide 12/13 hour later [not 12/11 hours later - H and M are moving "toward" each other this time] when the clock reads 2:00:50.4. Note that 12/11 + 12/13 = 288/143 = ~2.014 is slightly greater than 2. After an hour wait, a cycle is complete. The cycle then repeats.
So, with M bouncing back and forth and H jumping hesitantly forward, when will the hands next be upward vertical? There are two possible answers. First, when a multiple of 288/143 is also a multiple of 12. These are the even-numbered points of coincidence, at the ends of complete cycles. Second, they could coincide mid-cycle. That is, when 12/11 plus a multiple of 288/143 is a multiple of 12.
[288/143]n = 12m -- or -- 12/11 + [288/143]n = 12m
- 1
#328360 Give a monkey enough rope
Posted by bonanova
on 16 February 2013 - 05:48 AM
I am giving this puzzle verbatim from a book I read long ago. These days most everything I have ever done was long ago. But I digress. I simply don't trust myself to re-cast it into scintillating banter style. So if its tenor is archaic or arcane, the onus is off me. Enjoy.
A rope ran over a pulley; at one end was a monkey, at the other end a weight. The two remained in equilibrium. The weight of the rope was 4 oz/foot, and the ages of the monkey and the monkey's mother amounted to four years. The weight of the monkey was as many pounds as the monkey's mother was years old, and the weight of the weight and the weight of the rope were together half as much again as the weight of the monkey.
The weight of the weight exceeded the weight of the rope by as many pounds as the monkey was years old when the monkey's mother was twice as old as the monkey's brother was when the monkey's mother was twice half as old as the monkey's brother will be when the monkey's brother is three times as old as the monkey's mother was when the monkey's mother was three times as old as the monkey was in paragraph 1.
The monkey's mother was twice as old as the monkey was when the monkey's mother was half as old as the monkey will be when the monkey is three times as old as the monkey's mother was when the monkey's mother was three times as old as the monkey was in paragraph 1.
The age of the monkey's mother exceeded the age of the monkey's brother by the same amount as the age of the monkey's brother exceeded the age of the monkey.
What was the length of the rope?
- -1
#328354 Why isn't this a legitimate answer?
Posted by bonanova
on 16 February 2013 - 03:48 AM
In theology Wesley defined "sin" as "willful transgression of a known law of God."
So, an act could be a sin or not, based on the actor's state of knowledge or intent.
Many logicians attribute the prefix "It is true that ..." or "It is the case that ..." to all declarative statements.
That permits a paradox to become instead a simple contradiction.
In American courts, there is a permissible disclaimer of "upon information and belief" that allows a witness to tell things as s/he knows them without saddling them with proving the truth of their statements.
If we take the liar's paradox as [possibly flawed] informal conversation, we get some added "outs" from the paradox.
- 1
#328341 Prof. Bonanova's Analogies
Posted by bonanova
on 15 February 2013 - 11:15 PM
Professor bonanova peeks in, wondering if there is a clue yet.
He certainly has none ...
- 2
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