040 - Greenjack

Some time ago, Farmer Joe made the mistake of gambling against one of his regular customers.

The game was Greenjack, a popular betting game in Serendipity. It is played with a deck of only 16 cards, divided into four suits: Red, Blue, Orange, and Green. There are four cards in each suit: Ace, King, Queen and Jack. Ace outranks King, which outranks Queen, which outranks Jack - except for the Green Jack, which outranks every other card.

If two cards have the same face value, then Red outranks Blue, which outranks Orange, which outranks Green, again except for the Green Jack, which outranks everything.

Farmer Joe, who is not the dealer, is dealt a card face up which both players can see. The dealer deals themselves a card, which they look at and then place face down. The dealer then makes three true statements which are capable of identifying which card is higher. If Farmer Joe correctly identifies which card is higher from the statements, he wins; otherwise he loses.

On this occasion, Farmer Joe was dealt the Blue King.

The dealer said:

1) My card would beat a Green King.
2) Knowing this, if my card is more likely to be a Jack than a Queen, then my card is a King. Otherwise, it isn't.
3) Given all of the information that you now know, if my card is more likely to beat yours than not, then my card is Red. Otherwise it isn't.

Farmer Joe got it wrong and lost the bet. Can you do better? Who holds the higher card?

039 - The Devil's Dice

Zephyr Cantrell possesses an unusual set of six-sided dice.

There are four dice in total. The faces of the dice each bear an integer between 1 and 24 inclusive. Each integer is used and none are repeated. Each of the dice has a different colour. The dice are perfectly weighted and each face of each die has an exactly 1 in 6 chance of being rolled.

The red die rolls a higher number than the blue die more often than not.
The blue die rolls a higher number than the green die more often than not.
The green die rolls a higher number than the yellow die more often that not.
The yellow die rolls a higher number than the red die more often than not.
The number 14 appears on the red die.

How are the faces of the dice numbered?

038 - Mornington Crescent

I was lucky enough while idling at Serendipity University today to witness an masterclass in the game of Mornington Crescent between Zephyr Cantrell and Urtha Bennett. Naturally you're well aware of the rules, but until you've seen it played by intellects of this calibre you've never really seen it played.

After the traditional round of drafting, and a clarification that yes, they were playing the Lyttleton variant, Zephyr opened with a Dutch runabout to Moorgate via Aldgate East, which personally I've never seen played before, and apparently neither had the rest of the audience, judging by the gasps. Equally surprising was Urtha countering with a fourfold blind through Euston/Warren/Goodge.

From there the two played a cat-and-mouse game across the Hammersmith & City line, with the highpoints being a Layman's Knee by Zephyr at Sudbury Town (with Egyptian Cross to Golders Green, no less), and an even more impressive triple crown for Urtha culminating at Blackfriars. This, mind you, after being scuttled at Baker Street, Knightsbridge and Shepherd's Bush - in that order!

However, all good things must come to an end, and on her eleventh turn Zephyr made the mistake of passing west at Paddington to avoid a Southwark/Putney Bridge pin without noticing the worrying state of the Embankment. Seizing the moment, Urtha dove in to make the final move and win the game.

What was Urtha's game-winning play?

037 - The Journey of Abernathy Gould

"Let me tell you a story," says Jacki Renquist as she leads Kent Dockland through the Logidyne Labs complex. "This happened during my grandfather's time."

"The great explorer, Abernathy Gould, came to western edge of a vast desert. She had with her her eight stalwart companions. Each of the nine travellers was driving an all-terrain car capable of travelling forty miles to the gallon - which was also the capacity of their cars' petrol tanks."

"When they reached the western edge of the desert, every car had a full tank of petrol, and each car carried nine extra gallon tins of petrol (that being the largest number of tins a single car was capable of carrying)."

"Under Gould's leadership, the nine travellers set out in a straight line east across the desert with the aim of Gould travelling the furthest distance east that she could manage, in the hope of finding.... something. All nine travellers returned safely, along with their cars, to the western edge of the desert at the conclusion of the journey. No additional petrol was acquired during the journey, no petrol was left unattended in the desert for any length of time (or, for that matter, with a car or driver to guard it), and none of the explorers travelled any distance on foot (as a journey on foot through the desert was said to spell certain death)."

"Gould later claimed that the distance she travelled into the desert was the greatest distance she could have achieved under the circumstances - which is lucky, as she only barely found what she was looking for."

Assuming Gould's claim is correct, how far east did she travel?

036 - What Kind Of Day Has It Been

Anwar Patel poses the following challenge to his students:

"In television, there are few episodes more important than the finale of the first season.  In addition to the normal drive to achieve high ratings, it also needs to compete against other season finales, leave viewers with a strong impression of the show to drive excitement for a second season, and, in the case of shows not lucky enough to be renewed, serve as a satisfying finale for the show's run."

"Can you match the following season 1 finale titles to the correct plotlines?"

1) The Neutral Zone
2) The Erlenmeyer Flask
3) Exodus
4) These Are The Days
5) Honeymoon
6) Fall Out
7) Kobol's Last Gleaming
8) Some Enchanted Evening
9) Sold Under Sin
10) A World Of His Own

a) Smoke is seen and a hatch is opened.
b) A man is killed while handing over a unique baby.
c) A playwright demonstrates unusual powers - including over a famous narrator.
d) Two men want to swap hearts.
e) An escape by six and an unmasking of one.
f) A parade, and a hardware salesman takes a new job.
g) Nine outposts go silent and three frozen travellers are found.
h) A doctor treats his ex-girlfriend's new husband.
i) A woman finds an arrow and a man visits an opera house.
j) Children match wits with an evil babysitter

035 - Grand Tour

Add lines to this grid so as to make a single closed path that touches every dot.

* Lines must be perfectly vertical or horizontal.

* Lines must begin at a dot and end at a different dot.

* For clarity, "single closed path" means a path forming a single uninterrupted line without beginning or end.

* Your path must include the lines already marked on the grid.

034 - Rational Pirates

Every morning the children of Serendipity thrill to the television adventures of Cap'n Redhook and his crew of perfectly rational sea-dogs as they sail the high seas in their clockwork ship The Razor of Occam.

Redhook's gang have an unusual way of dividing loot. The eldest pirate (in this case, Redhook) gets to propose a method of sharing the loot, and then all pirates (including the eldest) take a vote.  If a majority of pirates vote against the proposed split, the proposer gets thrown to the sharks, and the new eldest pirate proposes a new split, and so on until a split of loot is accepted.

In today's episode - Attack of the Cybersquid - Cap'n Redhook and his gang have looted 100 pieces o' eight from their nemesis, Admiral Goldbelly.  When it comes time to split the loot, what is the largest number of pieces o' eight Redhook can retain for himself?

Additional information:
* There are five pirates in Redhook's crew, including Redhook.
* All five pirates will vote so as to maximise their personal gain.  None are bothered by feeding their crewmembers to the sharks.
* Pieces o' eight can't be divided into fractions - the number of pieces o' eight each pirate gets must be an integer.
* Tied votes are resolved in favour of the proposer.

033 - Diggings

The original inhabitants of Serendipity are the cause of much speculation among archaeologists. Completely vanished by the time of the first European settlers, we only know them through the artifacts and art that they left behind.

The attached image is typical of the hyper-detailed cave art found in diggings in the Fortune Woods, and is often shown to new archaeology students. On a first view, many students claim that it shows humanoid figures with weapons, animals, and a wheel, but SU's Chair of Archaeology, Urtha Bennett, takes great delight in telling them how wrong they are.

What does the cave art actually depict?

(NOTE: It may not be possible to solve the puzzle using the image below.  A higher resolution version is attached to the email copy of this puzzle and is available on request.)

032 - Three, Four and Five

Detective Kent Dockland attends at Logidyne Labs to interview Jacki Renquist about the work she's been doing with Hillary Black.

However, he finds Jacki busy in the chemicals storeroom.

"I don't have time for you today, Dockland," Jacki snaps. "I need to measure out four quarts of umbrafan, but one of the idiot new recruits broke my measuring containers. All I have is the barrel of umbrafan, a three quart container, and a five quart container."

"That's a fairly trivial problem, ma'am," said Dockland stoically, and then explained to her how to solve it. "And now maybe you have time for an interview?"

How did Jacki measure out four quarts of umbrafan?

031 - Crackling

Farmer Joe keeps jars full of pre-prepared pork crackling to serve as entrees at Farmer Joe's BBQ Porkatorium.  One jar contains honey-marinated crackling, one jar contains peppered crackling, and one contains a mixture of both.

Unfortunately, Zephyr Cantrell, a regular customer with an odd sense of humour, has switched the labels on Farmer Joe's crackling jars.  According to Zephyr, each of the three jars now bears an incorrect label.  The three labels are "Honey-Marinated", "Peppered" and "Mixed".

Farmer Joe is keen not to waste any of his beloved pork crackling.  Unfortunately, the only way to tell honey-marinated crackling from peppered crackling is to taste it.

From the jar bearing which label should Farmer Joe taste a piece of crackling in order to correctly re-label all three jars?

030 - Seven Bridges

Serendipity 1's hit TV show Seven Bridges follows the romantic misadventures of a group of attractive singles living in the fictional community of Seven Bridges. The community sprawls across both banks of the Gellis River and also includes two islands in the centre of the river. The riverbanks and islands are connected by a series of bridges, as shown in the attached image.

Famously, the show claims that it is impossible to cross all seven bridges in one voyage without retracing your steps or crossing the same bridge twice, regardless of where you start or finish - a metaphor for life's missed opportunities.

Last year a proposed spin-off, Thirty-Nine Bridges, set on an archipelago of islands, was briefly mooted before being nixed during development.

Is Seven Bridges correct? Is it impossible to cross all seven bridges, as shown in the attached image, without crossing a bridge twice?

And what about the proposed layout of Thirty-Nine Bridges? Is it possible to cross all thirty-nine bridges without crossing a bridge twice?

NOTE: It is not permissible to partly cross bridges - any crossing of a bridge must begin at one end and finish at the opposite end.

029 - The Devices of Serendipity

Although there are, to date, 53 known Devices, only five are on display in the Serendipity Museum of Local History.

They are stored in a line of five display cases in a high security area of the museum, numbered 1 to 5 from left to right. Each of the five, as is the case with all known Devices, is marked with one of the runic characters of the local ancient language, and each possesses a single unique unexplained property.

1) There are two cases between a Device that emits random ultrasonic noises when exposed to sunlight, and the Device induced by Agnes Tutwillow on its right.

2) The Device that determines the number of iron molecules within 3.8 metres is in the case directly to the left of the Device induced by Yolanda Harkness.

3) There is one case between the Device that anaesthetises its holder, and the Device induced by Jonathan Horacek on its left.

4) The device induced by Brierly Smith is next to The Wheel.

5) The hole punch is not in the fifth case.

6) The Device that makes documents unintelligible is directly to the right of the protractor.

7) The Crossroads is not in the first case.

8) There are two cases between the audio cassette and the protractor.

9) The Crossroads is next to the hole punch.

10) The Knot is next to the pocket calculator.

11) There are two cases between the Device induced by Emilio Argento and The Bear.

12) There is one case between the device induced by Agnes Tutwillow and The Bear on the left.

13) The Wheel is not in the first case.

14) Although one of the Devices boils any liquid it is immersed in, it is not the flashlight.

15) The Thorn is not the pocket calculator.

What does The Knot look like, what does it do, which case is it in, and who induced it?

028 - Hagiography

Found left on a street corner:

C E F G
C E F G
C E F G
E * * *

What letters do the three asterisks represent?

027 - Heavier Metals

Logidyne Labs is testing a Device. One of the side effects of the Device is to minutely increase the mass of certain alloys in its immediate vicinity.

A scalpel was used in the Device Room today. Per Logidyne procedure, the scalpel will now have to be quarantined until it can be determined to be safe. However, a clumsy assistant has mixed up the scalpel with eight other scalpels.

The nine scalpels are identical in every way, except that the scalpel from the Device room will be heavier than the others.

Using a pair of balancing scales, how can the heavy scalpel be identified in only two weighings?

026 - Rashomon

This special puzzle is only available to players via email.

Please refer to the email version for puzzle details.

025 - Blowout

Farmer Joe has 15 four-hour candles.

At 7 pm, Farmer Joe lights all his candles.

At 9 pm, he extinguishes one third of them.

At 10 pm, a breeze blows out half of those still burning.

At 11 pm, how many candles does Farmer Joe have left?

024 - Ave Caesar

"Are these all of them?" asked Detective Dockland.

"Yes," replied Hillary Black. "I've given you a copy of every other document in the safe on the night of the robbery. I should warn you, though, they're all encrypted."

Dockland glanced briefly at the top document in the stack. "I don't think much of your idea of encryption."

"Oh, that one's not serious encryption. She just does them that way for fun," said Hillary.

Dockland paused, and looked at the document longer, before adding, "She's right, in that the math problem is't very hard either."

What is the answer to the math problem Dockland is referring to? The document reads, in full:

DY RSVVKBI

GYBU MYXDSXEOC. CY PKB KVV DOCDC YX DRO NOFSMO RKFO ZBYFON XOQKDSFO. GO KBO CDSVV RYZOPEV YP MBKMUSXQ DRO KMDSFKDSYX COAEOXMO GSDRSX DRO XOHD GOOU. DRO DOKW SC ECSXQ LBEDO PYBMO LED S CDSVV DRSXU DROBO WECD LO KX OKCSOB GKI. SD'C VSUO PSXNSXQ DRO CEW YP KVV ZYCSDSFO SXDOQOBC LODGOOX YXO KXN YXO REXNBON SXMVECSFO - DROBO SC XY XOON PYB DONSYEC KNNSDSYX GROX IYE UXYG DRO CRYBDMED. KXIGKI S RYZO DY RKFO WYBO XOGC XOHD DEOCNKI.

LOCD BOQKBNC

TKMUS

023 - Bookworm

A bookworm has made its way into the Serendipity Municipal Library, and set its sights on the ten-volume Journals of Abernathy Gould, which are organised in numerical order, cover to cover, on one of the Library's lower shelves.

Each volume of the journals has 1,000 pages. If the bookworm starts eating at page 1 of volume 1, and finishes at page 1000 of volume 10, how many pages will it have eaten through?

022 - Movie Business

Anwar Patel has another challenge for his students.

"In the history of cinema, our filmmakers have created a great many fictional characters. But not all characters are human; over the years we've seen a wealth of memorable corporations brought to the screen. Can you name the movies that these fictional corporations appeared in?"

1) LesterCorp
2) Tyrell Corporation
3) Initech
4) Weyland-Yutani Corporation
5) Jackson Steinem & Co
6) Rekall
7) Cyberdyne Systems Corporation
8) Monumental Pictures
9) Omni Consumer Products
10) Hudsucker Industries

021 - Jigsaw

How many?  (Less than ten.)

020 - Equal Opportunities

Detective Kent Dockland is questioning Hillary Black about the recent break-in at her offices.

"Can you tell me a little bit about your business?" he enquires.

"We're a consulting firm," says Hillary. "We mostly do work for Logidyne Labs, a research and development company."

"And how many people are employed here?" asks Kent.

"Well, each male worker has one fewer female co-worker than he does male co-worker," says Hillary, "and each female worker has two male co-workers fewer than twice the number of her female co-workers."

"Thank you, ma'am," says Kent. "That's very helpful."

How many people are employed at Hillary's consulting firm?

019 - Age Detective

Responding to an urgent call, Detective Kent Dockland attends the offices of Hillary Black, where a burglary has been reported.

Hillary, though, is unimpressed. "Dockland?" she says. "I've heard you've got a bad reputation on the police force. Why shouldn't I send you back and request a good detective?"

"I am a good detective, ma'am,' says Dockland.

"Well, then," says Hillary, "tell me this: how old are my daughters?"

"How many daughters do you have?" asks Dockland.

"Three," says Hillary. "The product of their ages is 36, and the sum of their ages is the same as the number on my ID badge."

Dockland looks at Hillary's ID badge. "I'm sorry, ma'am," he says. "I can't tell you the answer to that question given that information."

"Oh, of course you can't!" says Hillary. "My apologies. I should have added that when I went into labor with my youngest daughter, both of her sisters were running around the back yard."

"Well, then, that's easy," says Dockland, and tells her the answer.

"Well, Detective, it seems I've been mistaken about you," says Hillary. "Let me tell you about these documents that were stolen..."

How old are Hillary's daughters?

018 - Happy Families

Anwar Patel is Professor of Media at the Serendipity University. He set the following challenge for his students.

"Television has given us a rich history of characters bound by family ties. For each of the families below, can you provide their surname and the television show they come from?"

1) Gomez, Morticia, Pugsley, Wednesday, Fester
2) Ross, Monica, Jack, Judy
3) Willie, Kate, Lynn, Brian
4) Dick, Sally, Harry, Tommy
5) Chris, Meg, Lois, Peter, Stewie
6) Nick, Tony, Joey, Blossom
7) Marcia, Carol, Greg, Jan, Peter, Cindy, Mike, Bobby
8) Danny, D.J., Stephanie, Michelle

017 - Pork Grill

Tired of complicated inter-jurisdictional swinekeeping legislation, Farmer Joe has converted his pig farm into a restaurant. Farmer Joe's BBQ Porkatorium is now the premier pig-themed eatery in Oddsville.

Farmer Joe's secret is his ability to cook pork chops in record time, despite the tiny size of the kitchen's pork grill.

The pork chops used in Joe's delicious Porkgasm Surprise need to be grilled for 10 minutes on one side, and then 10 minutes on the other. The pork grill can only hold two chops at once.

Nevertheless, when three customers simultaneously order the Porkgasm Surprise, Joe is able to prepare it surprisingly quickly. What is the fastest time in which Joe can complete the grilling of three pork chops on his pork grill?

016 - Brevity of Communication

Kent Dockland doesn't get on well with his co-workers at the Serendipity Police Department. Today, as he's trying to finish some incident reports on his computer, he's distracted by his co-workers loudly discussing the comparitive merits of cars, motorcycles, and speedboats.

Peter Bernard, the loudest, meanest cop on the force, spots Kent at his computer. "Hey Kent!" he yells. "What kind of vehicle do YOU like?

"Here's the thing, Peter," says Kent. "This isn't news. You understandably really like cars or motorcycles. But I have to finish this incident report, it's due today, and you and your idiot friends aren't helping."

Peter scowls. "Don't be a loser, Kent. The report can wait five minutes. What's your vehicle of choice?"

Kent stares at Peter, and says, "I just told you."

What is Kent's favourite kind of vehicle?

015 - Shifty Triangle

Documents have been stolen from Hillary Black's safe! Or have they?

Hillary has opened her safe this morning to find that her crucial documents have been moved around. At first she was sure there were some missing, but now she's not certain.

Always a stickler for patterns, Hillary kept her oddly-shaped documents arranged in the shape of a triangle. And indeed, they're still in the shape of a triangle.

The current shape of the documents is triangle A in the attached image.
Yesterday, Hillary had the documents arranged as triangle B.

The purple square document appears to have vanished, but the triangles look the same.

Has anything actually been removed? And if so, what's the explanation for the similarity of the triangles?

014 - Logidyne Hats

Logidyne Labs, a research and development company based in the city of Serendipity, is welcoming its newest round of recruits today. Before they can start work, Logidyne's head researcher Jacki Renquist subjects the three recruits to an unusual test.

Jacki instructs the three recruits to be seated, and then places a hat on the head of each recruit, such that each recruit can see all of the other hats, but none of them can see their own.

"Each hat is either white or blue," says Jacki. "There is at least one blue hat. You may not talk amongst yourselves, or communicate in any way. You may not remove your hat, or otherwise view its colour. None of you may start work until one of you correctly declares the colour of your own hat. If any of you incorrectly guess the colour of your hat, you will all three be fired. You have all been hired on the basis of your perfect command of rational thought, and therefore I am sure you will be able to start work today."

Jacki was correct and the recruits started work shortly thereafter.

How did they solve the test?

013 - Jason D

Hillary Black keeps her most valuable secrets in a locked safe. Unlocking the safe requires a 12-letter-long passcode.

Unfortunately Hillary isn't good about keeping her passcode secret. She wrote it on a piece of paper, and then dropped the paper outside her office, where it's been trodden on and damaged. A lucky burglar has found the scrap of paper and is now trying to make sense of it.

The first six letters of the code are illegible, but the last six are:

J A S O N D

What is the complete code likely to be?

012 - Of A Certain Age

Damon Wintric doesn't like to reveal much about himself.

When a reporter recently asked him how old he was, he replied:

"If to my age there added be,
One half, one third, and three times three;
Six score and ten the sum you'll see,
Pray find out what my age may be."

By the time the reporter had started working out the clue on a piece of paper, Damon Wintric had already left.

How old has Damon claimed to be?

011 - Calendar of Cubes

Hillary Black, a consultant horologist working in the city of Serendipity, is fascinated by calendars and likes to use unusual ways of displaying the date.

When it comes to showing what day of the month it is, she uses a pair of custom-made cubes.

Each morning Hillary moves these cubes so that the front faces of the cube show the current day of the month. The format is always two digits, with the first day of the month being 01, all the way through to the month's end, so that the seventh day of the month would be shown as 07, and the twenty fifth 25.

How are the cubes marked so as to allow Hillary to use them this way?

010 - Prisoners and Switches

Twenty-three prisoners are imprisoned in an unusual prison. They are to be imprisoned until the warden of the prison decides to set them free.

The warden meets the prisoners as they arrive and tells them about a special room in the prison. In the room are two switches, each of which can be set either an "up" position or a "down" position. The switches are not connected to anything, and the warden does not tell the prisoners whether either switch is currently "up" or "down".

"I am about to give you an hour to plan, talking amongst yourselves," says the warden to the prisoners. "After that, you will be incarcerated in separate cells with absolutely no means of communication."

"From time to time during your imprisonment, I will select one of you at random and escort that prisoner to the switch room. The prisoner I select must select one, and only one, of the two switches and reverse its position. Then he will be led back to his cell. This is the only way in which the switches will be flipped; they will always be in the position that the last prisoner to visit the room left them in."

"The method by which I select a prisoner will be totally random and it may result in the same prisoner being selected several times in a row."

"At any time that a prisoner is in the switch room, he or she may announce to me, 'We have all visited the switch room.' If that prisoner is correct, you will all be set free. If they are incorrect, you will all be executed in a particularly painful manner."

What is the fastest way for the prisoners to win their freedom, without the slightest risk of being executed?

009 - Proving The Rule

In front of you are four cards. Each card has a letter or number printed on the face-up side. The cards read, in order:

A
Z
4
9

In the deck that these cards have been dealt from, all of the cards have a number on one side and a letter on the other.

If I told you that there was a rule, that cards which have an "A" on one side always have a "4" on the other, which two cards would you turn over to attempt to disprove the rule?

008 - Petals Around The Rose

In the game Petals Around The Rose, five regular six-sided dice are rolled, and players are challenged to give the "Petals Around The Rose" answer for the result.

For instance, the following dice rolls produce the following correct answers:

3, 5, 5, 5, 6 : the answer is fourteen
2, 6, 2, 1, 4 : the answer is zero
4, 3, 2, 1, 3 : the answer is four
6, 5, 6, 2, 2 : the answer is four
6, 3, 6, 5, 4 : the answer is six

There is only one correct answer for any given roll.

On a roll where the dice show 1, 3, 6, 5, 6, what is the "Petals Around The Rose" answer?

007 - Poison Pills

While captured by the evil Dr Apocalypse, you are presented with a terrifying deathtrap.  In front of you are five seemingly identical bottles full of pills, and a set of scales.

"Four of these bottles," explains Dr Apocalypse, "contain harmless sugar pills.  Each of the harmless pills weighs 10 grams.  One bottle, however, contains deadly poison that will deliver you to a painful death. Each of the poison pills weighs 9 grams."

"You may open the bottles, look at the pills, and use the scales I have provided you with once and once only.  After you have made a single weighing of your choice, you must correctly identify the bottle of poison, or else be forced to eat a pill from it."

The scales are of the sort that return the total weight of everything placed on them (that is, pressure scales, not balancing scales).  All the pills are shaped identically, and you're not allowed to weigh a pill and then keep adding more while still checking the weight. Only one weighing of as few or as many pills as you want, at once, is allowed.

How can you be certain which is the poison bottle?  And what is the smallest number of pills you can weigh to arrive at that conclusion?

006 - Two Sons

In the town of Gentford, newborns are equally likely to be male as female.  Out of all inhabitants of Gentford who have at least one son, Gunther is typical.  He has exactly two children.  What is the probability that he has two sons?

(For the purposes of this puzzle, assume that gender options in newborns are limited to "male" or "female".)

005 - Five Daughters

Mary's father has five daughters: 1. Nana, 2. Nene, 3. Nini, and 4. Nono.  What is the name of the fifth daughter?

004 - Pigs In A Poke

Farmer Joe's Pig Farm lies on the border of Oddsville and Four Hills, and is thus subject to the laws of both towns.  Four Hills requires all pig farms to have exactly four pig pens, no more, no less.  Oddsville requires that all pig pens hold an odd number of pigs greater than zero.

Farmer Joe has 21 pigs.  How can he comply with both laws without moving his farm, changing his business, or gaining or losing pigs?

003 - The Bridge and the Torch

Four people come to a river in the night. There is a narrow bridge, but it can only hold two people at a time. Because it is night, a torch has to be used when crossing the bridge. Person A can cross the bridge in 1 minute, B in 2 minutes, C in 5 minutes, and D in 8 minutes. When two people cross the bridge together, they must move at the slower person's pace.  The group only has one torch between them.  How can all four people get to the far side of the bridge in 15 minutes or less?

002 - Isolate

Add additional walls to the pictured grid so that:

* It is broken into seven (7) discrete areas, of the following number of squares: 2, 3, 3, 3, 3, 4, 7.

* Each area contains exactly two gray cubes; no more, no less.

* Each grid intersection (marked by a plus sign) connects to at least 2 walls.

Lines may only be vertical or horizontal.

001 - The Mutilated Chessboard

Suppose a standard 8 x 8 chessboard has two diagonally opposite corners removed, leaving 62 squares.

* Is it possible to place 31 dominoes of size 2 x 1 so as to cover all of these squares?

* Explain why without showing a picture of a chessboard.

About Serendipity Puzzles

Serendipity Puzzles is a private puzzling competition created by me, for friends.

Puzzles are made available each weekday by email. Each puzzle appears on this blog at 8 PM Australian Eastern Coast Time the day before it is due to go out by email. Answers are submitted by email to me. Correct answers score points on a leaderboard that is distributed roughly twice a week by email.

At this stage new players are welcome. To join, please email me at starfall2317, at gmail.

I reserve the right to not accept new players, to post puzzles at times of my choosing, to discontinue the puzzling competition at any time, and to accept or refuse answers entirely at my discretion.

Comments are disabled on this blog to prevent spoilers.