Your Favorite Brain Teaser

[2xDouble]

CURSE YOU BATMAN!!!

Umm....Try and solve this, Batman!

I have eyes but cannot see, ears but cannot hear, and nerves but cannot feel.

What Am I?

Terry Schiavo.

My riddle: You and 99 other people are being taken to some evil mastermind's lair, where each of you will be put in a line and have either a black hat or a white hat placed on your head. In the line, each of you can see all the people in front of you, but not any of the people behind you. The mastermind will start at the back of the line and go through the line asking each person for their hat color. Everyone who answers correctly will be freed; everyone who answers incorrectly will be shot. What's your best strategy?

Ask the guy behind you what color the hat is?

And mine was supposed to be a corpse, but I guess that works too.

I should expand a bit: you're not allowed to talk after the hats are placed on your heads, but you can hear what the people behind you say and whether they were right.

Oh, and I'm aware that I'm a terrible person.

Look at the hat as it's being put on your head. duh.
OR Answer correctly that you do not know the color of your hat. (although that will probably get you killed for being a smart-ass)
OR Look carefully at the line ahead of you and try to discern a pattern of distribution, while paying close attention to the answers behind you to confirm.
OR (Smart-ass answer #2): shake your head violently to remove the hat from your head, then answer correctly "I'm not wearing a hat". (you could modify this plan to get the hat into your hands, observe its color, then replace it)

 

[TazTheTerrible]

a river
EDIT: oops wrong page

Concerning the hat thing, is there any fixed number of black and white hats? I guess I'd go to stand all the way at the front (so that I'd be last) and then listen to what other people say. Whoever is all the way at the back probably bets on him having a hat of whatever colour there are most of, or which there are least of if he counts 49/50.

My fav riddle:
The billiard balls. There's 12 of them and one is either slightly lighter than the others or slightly heavier. You have a set of scales (ones that strike one way or the other, not indicate weight) and you get to weigh three times. By the end you have to be able to determine which ball is the odd one out and whether it is heavier or lighter.

Obviously the difference is too small for you to tell by guessing manually.

 

[erto101]

There is a car crash. The father is killed and the son is rushed to hospital. The boy is taken directly into surgery but the surgeon says

"I can't operate on him, he is my son."

How can this be?

The dead father is a priest. The doctor is the biological father.

OR

The son has two dads.

His mother is a surgeon... You sexist S.O.B lool.

Don't worry it's what the teaser is meant to do. Proves there is something wrong with society if people will go to these lengths before accepting or thinking of a female surgeon.

I did the exact same thing when I heard it.

guessed it at first glance my mom's a surgeon xD

 

[TotallyFake]

CURSE YOU BATMAN!!!

Umm....Try and solve this, Batman!

I have eyes but cannot see, ears but cannot hear, and nerves but cannot feel.

What Am I?

Terry Schiavo.

My riddle: You and 99 other people are being taken to some evil mastermind's lair, where each of you will be put in a line and have either a black hat or a white hat placed on your head. In the line, each of you can see all the people in front of you, but not any of the people behind you. The mastermind will start at the back of the line and go through the line asking each person for their hat color. Everyone who answers correctly will be freed; everyone who answers incorrectly will be shot. What's your best strategy?

Ask the guy behind you what color the hat is?

And mine was supposed to be a corpse, but I guess that works too.

I should expand a bit: you're not allowed to talk after the hats are placed on your heads, but you can hear what the people behind you say and whether they were right.

Oh, and I'm aware that I'm a terrible person.

Look at the hat as it's being put on your head. duh.
OR Answer correctly that you do not know the color of your hat. (although that will probably get you killed for being a smart-ass)
OR Look carefully at the line ahead of you and try to discern a pattern of distribution, while paying close attention to the answers behind you to confirm.
OR (Smart-ass answer #2): shake your head violently to remove the hat from your head, then answer correctly "I'm not wearing a hat". (you could modify this plan to get the hat into your hands, observe its color, then replace it)

You can see the hats of people in front of you. And the people behind you CAN communicate with you (you can overhear their answer to the nutjob), it's just the only information they can give is White or Black. The guy at the back names the colour which he sees an even number of, say, black. He has a 50/50 chances of dying. The guy in front counts the hats in front of him. If he sees an odd number of blacks, he must be black. The next person counts, if he sees an even number of blacks, he must be black. And so on. 99 people guaranteed to live, 50/50 chance of all 100 living.

 

[Queen Michael]

Here's my brain teaser:
Three women share a hotel room. They order a bottle of chapagne from room service. The room service guy knocks at their door, gives them the bottle, and gets a ten-dollar bill each from them since the champagne costs $30. When the room-service guy gets down to the lobby, the guy in the lobby says "You idiot, it costs $25, not $30! Go up and return $5!" So our friend room-service guy does that, but pockets $2 as a tip, since they won't be able to split $5 evenly between three women anyway. He gives a dollar to each woman.

That means every woman paid $10. Every woman got $1 back, so in the end every woman paid $9. And $9 times 3 equals $27. Add to that the $2 the rooms-ervce guy pocketed as a "tip" and we've got $29. What happened to the last dollar?

 

[shwnbob]

Time for his sons to get a job? I have no clue XD

I kind of fail at these, but I have one:

A woman is reading in her house by the sea. She gets tired, turns off all the lights, and goes to bed. The next morning, she opens the paper to read "2000 killed in boat crash." She then immediately jumps out the window and kills herself. Why?

I assume that she lives in the Lighthouse and they were killed because she turned off the light?

Bing bing bing!! Way to go!

Here's a tougher one:

A girl's mother dies, and at the funeral, she meets a nice young man. A week goes by... then the girl stabs her sister to death. Why?

Before you freak out, this is a question I was posed when I was in high school. One answer means you have some dangerous tendencies.

She wanted to go to another funeral to see the guy again.

 

[Uncreative]

Here's one for you computer scientists and logicians; (This is an actual interview question from Google)

You have 1000 bottles of wine, and one of them is poisoned, but you don't know which one.

At your disposal are 10 prisoners who are slated to die today, which you can use to figure out which bottle is poisoned.

The poison is relatively fast-acting, meaning it will kill the prisoner after a little while, but one could take a drink from all 1000 bottles before the poison would take effect.

How do you figure out which bottle is poisoned?

There are two possible answers to this riddle, one is a lot better than the other.

Ask the the man in jail for poisoning the wine?

computer scientists and logicians

Ah, right. Never mind.

 

[JokerCrowe]

Here's my brain teaser:
Three women share a hotel room. They order a bottle of chapagne from room service. The room service guy knocks at their door, gives them the bottle, and gets a ten-dollar bill each from them since the champagne costs $30. When the room-service guy gets down to the lobby, the guy in the lobby says "You idiot, it costs $25, not $30! Go up and return $5!" So our friend room-service guy does that, but pockets $2 as a tip, since they won't be able to split $5 evenly between three women anyway. He gives a dollar to each woman.

That means every woman paid $10. Every woman got $1 back, so in the end every woman paid $9. And $9 times 3 equals $27. Add to that the $2 the rooms-ervce guy pocketed as a "tip" and we've got $29. What happened to the last dollar?

The math in this brainteaser is really stupid! if you devide the womens' money by 3, they each payed 9 and 1/3 of a dollar, it ads up to 28, plus the 2 dolars the kid took as a tip. It's pretty simple math that they payed 30 dollars and the room-service guy comes back with 5 dollars because it was only $25. it's when you do the deviding that you get confused, because you shouldn't devide like that! BTW I'm not mad at you Queen Michael, it's just that I really don't like this kind of calculating. It's the riddle I'm mad at, not you...

 

[ezeroast]

Time for his sons to get a job? I have no clue XD

I kind of fail at these, but I have one:

A woman is reading in her house by the sea. She gets tired, turns off all the lights, and goes to bed. The next morning, she opens the paper to read "2000 killed in boat crash." She then immediately jumps out the window and kills herself. Why?

I assume that she lives in the Lighthouse and they were killed because she turned off the light?

Bing bing bing!! Way to go!

Here's a tougher one:

A girl's mother dies, and at the funeral, she meets a nice young man. A week goes by... then the girl stabs her sister to death. Why?

Before you freak out, this is a question I was posed when I was in high school. One answer means you have some dangerous tendencies.

so she could see the nice young man again at the next funeral

couldn't be bothered reading down to see if anyone else got it

Edit: yea way too late

 

[The_root_of_all_evil]

Tom Cruise has been married three times. How can this be?

I LOL'd.

OK, a turtle walks towards a door 2 metres away at a speed of 1cm a minute. After 5 minutes, a man tries to overtake him. He covers half the distance between him and the turtle, but in that time the turtle has moved forward a small amount.
The man breaks into a run, covering half the distance again, but the turtle has moved.
Now sprinting, he covers half the distance again, but it's still in front.

How can the man ever overtake the turtle?

 

[BringBackBuck]

My fav riddle:
The billiard balls. There's 12 of them and one is either slightly lighter than the others or slightly heavier. You have a set of scales (ones that strike one way or the other, not indicate weight) and you get to weigh three times. By the end you have to be able to determine which ball is the odd one out and whether it is heavier or lighter.

Obviously the difference is too small for you to tell by guessing manually.

1st weigh in: 6 balls on one scale - 6 balls on the other, whichever bunch are heaviest keep those 6 for the next weigh in
2nd weigh in: 3 balls on one scale - 3 balls on the other, whichever bunch are heaviest keep those 3 for the next weigh in
3rd weigh in: 1 ball on each scale, keep the third on the table, scales will tell you which is the heavier ball, if both balls are the same than the one left on the table must be the heaviest.

 

[Queen Michael]

Here's my brain teaser:
Three women share a hotel room. They order a bottle of chapagne from room service. The room service guy knocks at their door, gives them the bottle, and gets a ten-dollar bill each from them since the champagne costs $30. When the room-service guy gets down to the lobby, the guy in the lobby says "You idiot, it costs $25, not $30! Go up and return $5!" So our friend room-service guy does that, but pockets $2 as a tip, since they won't be able to split $5 evenly between three women anyway. He gives a dollar to each woman.

That means every woman paid $10. Every woman got $1 back, so in the end every woman paid $9. And $9 times 3 equals $27. Add to that the $2 the rooms-ervce guy pocketed as a "tip" and we've got $29. What happened to the last dollar?

The math in this brainteaser is really stupid! if you devide the womens' money by 3 they each payed 9 and 1/3 of a dollar, which when you ad it up becomes $30! It's pretty simple math that they payed 30 dollars and the room-service guy comes back with 5 dollars because it was only $25. it's when you do the deviding that you get comfused, because you shouldn't devide like that! BTW I'm not mad at you Queen Michael, it's just that I really don't like this kind of calculating. It's the riddle I'm mad at, not you...

Don't worry; the entire point was that people'd see how stupid the math was. THe most vital miscalculation was when I added the tip twice, that is, to the 25 for champagne+2 as a tip I add 2 dollars extra and claim that's the tip when actually the tip has already been added.

 

[Omegatronacles]

Tom Cruise has been married three times. How can this be?

I LOL'd.

OK, a turtle walks towards a door 2 metres away at a speed of 1cm a minute. After 5 minutes, a man tries to overtake him. He covers half the distance between him and the turtle, but in that time the turtle has moved forward a small amount.
The man breaks into a run, covering half the distance again, but the turtle has moved.
Now sprinting, he covers half the distance again, but it's still in front.

How can the man ever overtake the turtle?

He could keep moving instead of stopping to monitor the turtles progress

 

[JokerCrowe]

Tom Cruise has been married three times. How can this be?

I LOL'd.

OK, a turtle walks towards a door 2 metres away at a speed of 1cm a minute. After 5 minutes, a man tries to overtake him. He covers half the distance between him and the turtle, but in that time the turtle has moved forward a small amount.
The man breaks into a run, covering half the distance again, but the turtle has moved.
Now sprinting, he covers half the distance again, but it's still in front.

How can the man ever overtake the turtle?

By not running only half the distance every time?
if it's 1 meter to the turtle and he walks half the distance, he's walked 50 cm, run half the dinstance of that (=25), and you have run 75cm, sprint half that distance of that (12,5cm) and you're at 87,5cm, half of that, (6,25cm) and he's almost there! 93,75. unfortunaltely you will slow down so much that as long as the turtle is moving you can never catch up to him! (if you always run HALF the distance)
[sub]and how exactly do you RUN 2,5 cm?[/sub]

 

[The_root_of_all_evil]

He could keep moving instead of stopping to monitor the turtles progress

He's not stopping. The turtle's progress is being monitored.

By not running only half the distance every time?

You're getting close, but he's not actually stopping, he's accelerating the whole time. He doesn't have to run half the distance each time, but that's what's being monitored. And remember, the turtle is still moving forward in that time.

 

[Zersy]

Hey everyone! Post your favorite brain teaser. Also check back and try to answer other people's.
Here's mine:
You are on a journey to the village of truth. You come to a fork in the road with a sign that says village of truth and village of lie but no arrows to designate which way leads to which village. A man stands at the side of the road. He says that you can ask one question of him and from that answer you can try to figure out which way to go. However, you don't know which village the man is from. What do you ask him to get you to the village of truth?

Easy , Just ask him if he is a man. You already know he is man so if he says he is then he's telling the truth , if he says he's not a man then he's lieing.

That or we have a Transexual problem....

 

[Shanecooper]

Tom Cruise has been married three times. How can this be?

Cause he's insane? He's an alien? He needs help? take your pick

 

[DFish]

An easy one, and a hard one:

Easy:
There is a circular path 3 miles in diameter. At one point, two men stand back-to-back and walk away from each other along the path. A dog sets off clockwise from that point at 10 mph, runs to the man walking clockwise (who walks at 3 mph) then turns back and runs to the man walking anticlockwise (at 4 mph), then turns back again and so on. The men continue walking, and the dog continues running back and forth between them, for one hour. How far does the dog run?

Hard:
There is an island with 50 blue-eyed people, 50 green-eyed people, and the Shaman, who has brown eyes. Every night a boat arrives, and if a person knows they have blue eyes they must leave the island on this boat. However, no-one knows their own eye colour, there are no reflective surfaces to check your own eye colour, and they cannot communicate (and thus tell each other what eye colour they have). One day the Shaman says "I see a person with blue eyes". What happens next?

 

[DFish]

He could keep moving instead of stopping to monitor the turtles progress

He's not stopping. The turtle's progress is being monitored.

By not running only half the distance every time?

You're getting close, but he's not actually stopping, he's accelerating the whole time. He doesn't have to run half the distance each time, but that's what's being monitored. And remember, the turtle is still moving forward in that time.

The sum of an infinite series can be finite.

 

[DFish]

My fav riddle:
The billiard balls. There's 12 of them and one is either slightly lighter than the others or slightly heavier. You have a set of scales (ones that strike one way or the other, not indicate weight) and you get to weigh three times. By the end you have to be able to determine which ball is the odd one out and whether it is heavier or lighter.

Obviously the difference is too small for you to tell by guessing manually.

Read about Claude Shannon.