Riddled with Puzzles or Puzzled with Riddles?

I devised none of the following riddles/puzzles, but their presentation is my own. I have not done much scholarly legwork in attempting to track down their origin(s) or creator(s), but I assume such work to be difficult and time-consuming, if not impossible. If you happen to have solid information in this vein, I will most certainly include it on this page (after sufficient double checking).

Each of these riddles/puzzles describes the mental task you must complete honestly and without trickery. The solution will not depend on some abhorrent pun or loophole. Enjoy!

  1. A family of 4 has the odd task of crossing a dark tunnel with one gas lantern. The problem is that there is only enough gas for the lantern to light for 12 minutes. They cannot travel through the tunnel without the lantern. To add to the trouble, the tunnel is very narrow, and at most 2 family members can go across at a time. Yet another constraint is that each family member takes a different amount of time to cross. Dad takes 1 minute. Mom takes 2 minutes. Older sister takes 4 minutes. Kid brother takes 5 minutes. When 2 people go across, they travel at the speed of the slowest member of the party. How do they all get across before the light goes out?
  1. River crossing problems… It will be helpful to use objects to represent the people or things discussed in the following problems. REMEMBER: Boats can’t row themselves!
    1. Who hasn’t heard of that lonely farmer trying to get across the river on his lonely boat along with a sheep, a bag of grain, and a fox? “Why the fox?!” you cry in protest. Even though these objects/creatures are completely incidental, let’s at least make an effort to court reality and reasonableness. 
Same farmer, same river, same boat, different organisms. Now he’s trying to bring across his prize hen, a bag of prize corn, and his prizeless tomcat. For no good reason, he can only take one of these across in his little paddle boat at a time. To add to our farmer’s woes, the hen has an appetite for corn, and the cat has an appetite for foul. When left alone, these creatures can be expected to act on their hunger. How does the farmer get across with all of his possessions uneaten?
    1. A new party has arrived at this same confounded river. Originally, this party was said to be made up of 3 missionaries, and 3 cannibals. For reasons of avoiding the racist, imperialist, religious, and unnecessarily controversial implications of this party, we will say that the original reporter had gotten it all wrong. 
The actual story takes place in an apocalyptic nightmare where some government/corporate (pick your favorite enemy) plot gone wrong created an outbreak of a mutant zombie virus. A party of 6 dear friends is racing out of a zombie-ridden jungle to seek haven in a nearby-town with a strong outpost of human survivors. Also in this town is a courageous scientist who has just isolated the antidote to this horrible plague. 3 of our desperate party of 6 have had the misfortune of contracting the zombie virus and are going through the preliminary stages of infection, but there is still hope! As long as they all can get to the town on the other side of a vast river before the advancing jungle zombies hunt them down, they may all survive.
In their darkest hour, fate smiles upon our party in the form of a small row boat that can help them cross the piranha-infested river. The boat is only big enough for 2 people to cross at a time. Even though the 3 infected individuals have enough of themselves left to focus on the task of crossing the river and rowing if necessary, they can’t completely resist the urge for human flesh. If at any time the number of infected people on one of the river banks exceeds the number of uninfected people, then the proto-zombies will give into their hunger and devour their uninfected companions. How can our 6 safely cross the river?
    1. As strange as the zombie tale was, a new party of travelers approaches this bewildering river with even odder restrictions. Fortunately, humanity saved itself against the zombie plague, and society is rebuilding itself. People breathe a sigh of relief now that looming apocalypse has been replaced by the “tolerable” outrages of business-as-usual for human beings (you know: greed, fighting, hate and fear – just enough to recognize this society as human, yet not enough to grind the machine to a halt). Where’d the preachy, preachy come from? Sorry. We’ll save the puzzle of “fixing” society for later…
An extremely dysfunctional family has just arrived at our river. Our crazy Brady bunch consists of a newly married couple with each spouse having 2 pieces of baggage in the form of young flesh and blood from a previous marriage. Dad has 2 boys, and Mom has 2 girls. Unfortunately for our newlyweds, marriage #2 is more of a food fight than a picnic and more of a mad dash for a departing bus than a walk in the park. The children are to blame. The boys hate their stepmother, and the girls hate their stepfather. The little brats are doing everything they can think of to stamp out the flame of love burning dimmer and dimmer in their parents’ hearts.
Dad naively thought that a camping trip could bring the clan together. All that the trip actually accomplished was the flaring up of emotions and the poor family getting lost in the woods. To make matters worse, the family now has the added stress to have encountered a policeman escorting a dangerous fugitive. The silver lining in this cliché – I mean cloud – is that the policeman knows how to get back to their camp and is heading that way himself. The rusty lining is that the way back involves crossing a damned (unfortunately un-dammed) river in a dinky row boat for no more than 2.
After some discussion, the motley crew realizes that getting everybody across this river isn’t going to be a cakewalk or a moonwalk. The kids aren’t strong enough to row against the current by themselves, so at least one adult must be in the boat to row. The policeman’s dangerous cargo adds to the complication. The policeman decides that the prisoner cannot be trusted to be left alone with any member of the family without the policeman’s presence for fear that she (That’s right! She. I bet you assumed the prisoner was a man. I did until just now when I turned him into a woman by the magic of pronouns – much easier than an operation.) will take a hostage and escape. The prisoner can be left all by herself on one side of the river, however, since the policeman can keep a gun sight on her from afar and shoot at the sign of any suspicious movement.
There’s one more snag. The parents are embarrassed to admit that should their children (one or both) be left alone with the opposite parent without the company of their own parent, the little monsters might push the other parent into those deep and treacherous waters. Get it? One or two boys can’t be left on a riverbank with Mom unless Dad’s there, and the same goes for the girls and Dad. That’s it. How do they all get across?
  1. A sadistic maniac not unlike the Saw guy has abducted a group of people and plans to execute them should they fail his logic test.
    1. His first social experiment is with 3 people. Once they come to from their gas-induced slumber, a surprisingly nasal and effeminate male voice begins talking from a loudspeaker protruding from the ceiling of their small metallic prison. 
“I bet you wish you weren’t such bullies in high school now!” shrieks the whiney voice.”
The three middle-aged professionals let out a collective groan as their tormentor continues his ridiculous sermon.
“As punishment for all of the teasing and beatings that I had to endure during those torturous years, your lives now belong to me. I will extinguish them without reservation, but I will give you a chance to preserve your pathetic existences. Your only hope for salvation is quick-thinking and solidarity, both of which I know you lack. Bwa ha ha ha!
“You will be taken out into the yard one at a time by my faithful servant, at which time a hat will be placed on your head. The hat will either be black or white, but you will not know which or be able to see. You will each stand in a straight line facing away from the doorway you just exited. The first person out will see only the opposite wall. The second person out will see the back of the first person. The third person out will see the backs of the first two. Once all three of you wretches are standing out in the yard (handcuffed as you are now), I will ask you each one and only one question to which you must provide the correct answer, lest I shoot you in the head. The question is: ‘What color is your hat?’

"Should you say anything other than ‘black’ or ‘white’ in response to this question, everyone will be shot. Should you make any attempt to communicate to your partners in any way, everyone will be shot. Should you do anything I can interpret as a signal – and I have a pretty wild imagination – everyone will be shot.
“You have 15 minutes to conference before the test is under way. I will comfort you in the knowledge that there is a guaranteed way for you to save all but one of your number, who has not but a 50% chance of survival. I cannot be completely benevolent to such cruel enemies, after all.”
What does the grudge-holding and murderous nerd mean by all of this? How can our three victims play by these insane rules while guaranteeing the survival of at least two? Can you figure it out in the 15 minutes that they have?
    1. After the three ex-bullies managed to escape this lunatic unscathed, he rounded up 10 more faces from his past. This time the victims were from his middle school days, where the hurt was deeper and the bullying was more severe. Although he presents them with the same exact test as he presented the 3 before them, he figures that it will be much harder for the 10 to figure out a way of saving their own skin. Surprisingly, 9 of the 10 need not fear death if the group adopts and applies the proper strategy. As before, one of their number will be coin flip away from life or death. What must our 10 abductees do to save at least 9 and hopefully the tenth? They get an hour to writhe around in problem-solving purgatory before their moment of intellectual judgment.
By the way, what has to be the case for the all three in (a) or all ten in (b) to survive? Could our villain guarantee the survival of everybody provided they solve his puzzle, or must he leave being a murder up to chance?

  1. Get 16 matches, toothpicks, or something similar. With them, represent the following equation: I + I I + I I I = I I I I
This equation says that 1 + 2 + 3 = 4, which simply ain’t true. Move one and only one of the sticks in that equation to produce a statement that a student of arithmetic would not argue with. You can’t touch the “= 4” bit, so that means you’ve got to come up with 4 on the left somehow.

  1. Here’s a toughie. You have 12 billiard balls. One of them is known to be a different weight than all of the rest. How can you use a balance scale (of the kind that blind lady on the courthouses holds) to isolate the ball of different weight if you only get 3 opportunities to weigh different quantities of balls. Not only must you find which ball doesn’t have the proper weight, you must also know whether it is too heavy or too light. Get under weigh! (I only promised that problems would not rely on abhorrent puns for their solution; I didn’t promise that I would not make any for their own sake.)
  1. You are dreaming. It is dark. You can see nothing. All of a sudden, you hear a click as somebody pulls the chain of a solitary light bulb, faintly illuminating a vast, yet narrow sterile hallway. You seem to be outside of space, observing the hallway while not truly in the hallway at the same time. The nondescript person in nondescript clothing takes a step forward and turns on another light with the same reverberating click. He solemnly continues down the hallway, with each step another click and even more light. For what seems like an eternity this continues until finally you hear foot steps with no more clicking. The hallway is blindingly light as a result of the 1000 clicks you just counted in your head.

Another drone enters the hallway where the first had entered 1000 clicks ago. She walks past the first light bulb and proceeds to the second, whereupon she turns it off with a click. Another two steps and she turns off the 4th light bulb, and so on as she recedes down the hallway turning every other lightbulb off.

This odd ceremony is far from over, and you are helpless but to observe the strange proceedings. Only after waking can you bring this dream to your analyst who will insist that the compulsive behavior exhibited in this dream is simply your infantile wish fulfillment of presenting the doctor (i.e. the parent) with material for analysis. The analyst knows better than to proceed by treating you as a compulsive neurotic. She informs you that the material of the dream itself acts as a screen to the deeper meaning that your occasional obsessive compulsive behavior of an anal retentive type is actually compensating for your true anal expulsive character. It is from this conflict that the treatment to your neurosis must proceed.

Lucky for you, all that psychobabble is yet to come. You’re still locked in this sterile and boring nightmare. A third person enters the quiet hallway and walks past the first and second light bulbs to pull the chain of third. It goes off. Three more steps and the automaton pulls the 6th light, turning it on. The cord of every third light bulb is pulled in this fashion, and you silently give thanks that this proceeding wasn’t quite as monotonous as the previous 2.

Before the third person or android has finished its insane task, a fourth enters the hallway. Predictably, it passes the first three light bulbs to pull the cord of the 4th. Moving faster than its predecessors it moves to the cord of the 8th, the 12th and so on. It isn’t long before a fifth android enters your nightmare to pull every 5th cord.

Android after android enter the hallway, each behaving as you expect them too. The boredom has almost caused you to fall asleep within your dream by the time the 1000th android pulls the 1000th cord, turning it off. The silence of the hall without footsteps and clicking overwhelms you, and you wake up. It’s not time to go to work yet, and you reflect on that strange dream. Some lights were left on by the end of that mathematical proceeding, but not many. “How many were left on?” you wonder, “And which ones?” Setting paper to pencil or pencil to paper you resolve to find out.

  1. 7 lily pads. 6 frogs. 3 that are dark on the right with 3 on the left that are light. If frogs were to hop only on pads that were empty and allowed to hop over no more than one frog of the other color, how would the light trade places with the dark? They can only move forwards, where for-wards is to-wards the starting position of the frogs of the opposite color.
  1. Charles Lutwidge Dodgson, who is more familiar by a name he named himself, was a master puzzle-smith among his many talents. He created a game called doublets, which involves transforming one word into another by the following process: CAT > cot > dot > DOG. Each step must involve the transformation of only one letter, and each step must produce a Scrabble-friendly word in the English language. The previous example was achieved using 2 “links”. 
Since Lewis Carroll was a gentleman, he probably would not encourage his readers to embark upon the alchemist’s task of transforming SHIT into GOLD by this process. Not a gentleman myself, I challenge you to accomplish this feat in 5 “links” or less.
  1. There are 2 separate rooms with no windows. You are in a room with 3 light switches. There are no windows, and just a solid door. In the other room (which you cannot see), you know there to be 3 light bulbs. Each of the 3 switches controls exactly one light bulb in the other room, but which one they control is unknown. Your task is to use the switches in such a way as to know the light that each switch controls when you leave the switch room and enter the light room. (no going back and forth; you only get one shot). 
This one is infuriating in the seeming impossibility of the task. Many of the other puzzles presented here are more approachable by strategy or systematic thought. This one depends on clever epiphany.
  1. Sitting in a room with a front and a back, a spider’s positioned and poised to attack. A fly’s on the wall, a foot from the ceiling and opposite the wall from whence the spider will crawl one small foot from the floor. The walls with the creatures, 12 square feet as their features, have between them a floor that is dirty and when counted in feet measures thirty. Despite their positions from ceiling and floor, both bugs sit 6 feet from each wall and no more.
The spider is lazy, and while you think this is crazy, the shortest path to the fly is more than just shy of 42 feet; it’s got that figure decidedly beat. If it can crawl on any surface it chooses, what is the shortcut the arachnid kid cruises?

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