Logic Riddles - Page 4

^Just want to say +1 to the above. I did the calculations a few days ago and got the same result, but was too lazy to type it on the computer.

I can add that if you happen to dislike geometric series for some reason, you can find probability to win in scenario A in a different way, which is kind of neat imo =). Let Pbg denote the probability of black winning when black is HU with gray, and black is about to shoot. Pgb is the prob of black winning when gray is about to shoot.

Pbg = 1/3 + 2/3*Pgb
Pgb = 1/3*Pbg

Solving the above 2x2 system of equations yields Pbg = 3/7, Pgb = 1/7.

On October 25 2012 01:20 Art.Cascade wrote: Oh, I like these! Let me add two of my favourites. 8. Many will have heard this, but we can't miss out on the Monty Hall problem: You are in a game show, and can choose between 3 closed boxes. One of them contains a car, the other two are empty. You pick box number 1. The show leader then opens box number 2, and it is empty. The show leader then presents you with the option to switch to box number 3. Should you switch?

+ Show Spoiler +

9. An hour glass with all the sand in the bottom is places on a very accurate scale. The hour glass is turned and the sand start flowing down. Does the scale show more, less or same as before?

+ Show Spoiler +

What weighs more a pound of quarters or a pound of feathers lololol

lololo

Acting on an anonymous phone call, the police raid a house to arrest a suspected murderer. They don't know what he looks like but they know his name is John and that he is inside the house. The police bust in on a carpenter, a lorry driver, a mechanic and a fireman all playing poker. Without hesitation or communication of any kind, they immediately arrest the fireman. How do they know they've got their man?

On October 27 2012 15:39 dnagardi wrote: Acting on an anonymous phone call, the police raid a house to arrest a suspected murderer. They don't know what he looks like but they know his name is John and that he is inside the house. The police bust in on a carpenter, a lorry driver, a mechanic and a fireman all playing poker. Without hesitation or communication of any kind, they immediately arrest the fireman. How do they know they've got their man?

+ Show Spoiler +

On October 27 2012 17:03 Spicy wrote: Show nested quote + On October 27 2012 15:39 dnagardi wrote: Acting on an anonymous phone call, the police raid a house to arrest a suspected murderer. They don't know what he looks like but they know his name is John and that he is inside the house. The police bust in on a carpenter, a lorry driver, a mechanic and a fireman all playing poker. Without hesitation or communication of any kind, they immediately arrest the fireman. How do they know they've got their man? + Show Spoiler + is it because firemen have name tags?

no, they dont

On October 27 2012 15:39 dnagardi wrote: Acting on an anonymous phone call, the police raid a house to arrest a suspected murderer. They don't know what he looks like but they know his name is John and that he is inside the house. The police bust in on a carpenter, a lorry driver, a mechanic and a fireman all playing poker. Without hesitation or communication of any kind, they immediately arrest the fireman. How do they know they've got their man?

+ Show Spoiler +

On October 28 2012 08:37 kingpowa wrote: Show nested quote + On October 27 2012 15:39 dnagardi wrote: Acting on an anonymous phone call, the police raid a house to arrest a suspected murderer. They don't know what he looks like but they know his name is John and that he is inside the house. The police bust in on a carpenter, a lorry driver, a mechanic and a fireman all playing poker. Without hesitation or communication of any kind, they immediately arrest the fireman. How do they know they've got their man? + Show Spoiler + 3 women, one man ?

correct

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quarters i think

unless there's a trick

On October 28 2012 16:38 bigredhoss wrote: quarters i think

Not sure if serious

1) A girl sees with her own eyes how a man murders two people and then burns down their house.
Why doesn't she call the police?

2) The boss of a softwarecompany is murdered. Four employees have a clear motive.
While being interrogated they are recorded saying;

Bart: It was Tom.
Tom: It was Erik.
Stefan: It definitely wasn't me.
Erik: Tom is lying if he claims it was me.

Only one of these men is speaking the truth. Who killed the boss?

On October 28 2012 19:47 SolarM wrote: Show nested quote + On October 28 2012 16:38 bigredhoss wrote: quarters i think Not sure if serious

whatever dude i gave it a shot

On October 28 2012 19:55 jeffv8x_-_16 wrote: 1) A girl sees with her own eyes how a man murders two people and then burns down their house. Why doesn't she call the police? 2) The boss of a softwarecompany is murdered. Four employees have a clear motive. While being interrogated they are recorded saying; Bart: It was Tom. Tom: It was Erik. Stefan: It definitely wasn't me. Erik: Tom is lying if he claims it was me. Only one of these men is speaking the truth. Who killed the boss?

2) + Show Spoiler +

And another of my favourites, from TL actually.

100 damn smart and organised prisoners. The guards set up a room, with 100 boxes, and place the (unique) name of all prisoner in the boxes. The guard collect one prisoner at a time from his cell to the room with boxes, and let the prisoner open 50 of the 100 boxes, one after the other. If any prisoner fails to find his own name in any of the 50 boxes he opens, then all the prisoners are killed. If all prisoners manage to find their name in the 50 tries, then they all go free. They have time to prepare a strategy before the box-opening starts, but once the first prisoner is in the room opening boxes, no more communication between the prisoners is possible. The prisoners do not know in which order they will be called in the room, and the guards set up the room in the exact same way for each prisoner.

How can the prisoners maximise their chances to get free?

hint: they can get well above 10%.

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On October 28 2012 23:17 Rapoza wrote: Show nested quote + On October 28 2012 21:32 Art.Cascade wrote: And another of my favourites, from TL actually. 100 damn smart and organised prisoners. The guards set up a room, with 100 boxes, and place the (unique) name of all prisoner in the boxes. The prisoners are allowed to go into the room, one at a time, and open 50 of the 100 boxes, one after the other. If any prisoner fails to find his own name in any of the 50 boxes he opens, then all the prisoners are killed. If all prisoners manage to find their name in the 50 tries, then they all go free. They have time to prepare a strategy before the box-opening starts, but once the first prisoner is in the room opening boxes, no more communication between the prisoners is possible. How can the prisoners maximise their chances to get free? hint: they can get well above 10%. + Show Spoiler + 50% (first time cap) 1- They run a list with their names (alphabetic order); 2- Everybody memorize the next name; 3- They enter using alphabetic order; 4- Guy enters and piles opened boxes in a alphabetic order; 5- Trow box with his name away from pile; 6- Trow box with next name away from pile in the other side (if he finds it); 7- Next guy enters and searches for the box in the other side away from the pile. If there inst a box, search in the remaining not piled boxes; 8- Repeat step 4 -> 8 until its done.

I knew I should have been clearer!
The guards prepare the room in the exact same way for each prisoner. There is no way for them to communicate once they started opening boxes. And the prisoners don't get to choose in what order they enter the room.

I'll edit to be more clear, sorry.

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