Riddle #683

logic

One lightbulb and 3 switches

You're standing in front of a room with one lightbulb inside of it. You cannot see if it is on or off. Outside the room, there are 3 switches in the off positions. You may turn the switches any way you want to. You stop turning the switches, enter the room and know which switch controls the lightbulb. How?
You turn 2 switches "on" and leave 1 switch "off" and wait about a minute. Then enter the room, but just before you enter, turn one switch from "on" to "off". Once in the room, feel the lightbulb - if it is warm, but off, it has to be the last switch you turned off. If it is on, it has to be the switch left on. If it is cold and is off, it has to be the switch you left in the off position.
93.22 %
37 votes

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The Smith family

The Smith family is a very wealthy family that lives in a big, circular home. One morning, Mr. Smith woke up and found his gardener's body. He knew it was one of his employees who had killed him. So he asked them what they were doing in the morning and he got these replies. Driver: "I was outside washing the car." Maid: "I was dusting the corners of the house." Cook: "I was starting to make lunch for later." From the replies he knew who the killer was. Can you guess who it was?
The maid, because they lived in a circular house and she was apparently "dusting the corners" of the house at the time of the murder - the house is round, therefore it has no corners.
79.48 %
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logicprobability

Live or die probability puzzle

Hussey has been caught stealing goats, and is brought into court for justice. The judge is his ex-wife Amy Hussey, who wants to show him some sympathy, but the law clearly calls for two shots to be taken at Hussey from close range. To make things a little better for Hussey, Amy Hussey tells him she will place two bullets into a six-chambered revolver in successive order. She will spin the chamber, close it, and take one shot. If Hussey is still alive, she will then either take another shot, or spin the chamber again before shooting. Hussey is a bit incredulous that his own ex-wife would carry out the punishment, and a bit sad that she was always such a rule follower. He steels himself as Amy Hussey loads the chambers, spins the revolver, and pulls the trigger. Whew! It was blank. Then Amy Hussey asks, 'Do you want me to pull the trigger again, or should I spin the chamber a second time before pulling the trigger?' What should Hussey choose?
Hussey should have Amy Hussey pull the trigger again without spinning. We know that the first chamber Amy Hussey fired was one of the four empty chambers. Since the bullets were placed in consecutive order, one of the empty chambers is followed by a bullet, and the other three empty chambers are followed by another empty chamber. So if Hussey has Amy Hussey pull the trigger again, the probability that a bullet will be fired is 1/4. If Amy Hussey spins the chamber again, the probability that she shoots Hussey would be 2/6, or 1/3, since there are two possible bullets that would be in firing position out of the six possible chambers that would be in position.
93.98 %
42 votes

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Number one

How do you make the number one disappear by adding to it?
Add the letter 'G' and it becomes Gone.
89.96 %
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Leave 6

Take 9 from 6, 10 from 9, 50 from 40 and leave 6. How is it possible?
SIX - 9 (IX) = S 9 (IX) - 10 (X) = I 40 (XL) - 50 (L) = X
93.39 %
38 votes

logic

Catholic school

A young boy went to a Catholic school. During school he started goofing around, so the teacher called him out and sent him to the Pastor. Since this was a traditional school the boy would be spanked, but the Pastor believed in giving people a chance. He said, "If you can ask me a question about something you learned and I don't know the answer on the spot you will go free." The boy may have been lazy, but he was very witty. He asked, "What is it that you can see and I can see, usually every day, but God cannot see." The Pastor stood there, stumped. He couldn't figure it out because he strongly believed that God sees and knows all, and that there is only one God. The boy smiled and told him. What was it?
His own equal! We see our equals everyday, but since there is one God, he cannot see someone equal to himself.
93.39 %
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Infinite number of mathematicians

An infinite number of mathematicians are standing behind a bar. The first asks the barman for half a pint of beer, the second for a quarter pint, the third an eighth, and so on. How many pints of beer will the barman need to fulfill all mathematicians' wishes?
Just one.
94.24 %
44 votes

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Beggar's brother

A beggar's brother died, but the man who died had not brother. How could this be?
The beggar was a women.
93.55 %
39 votes

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The casino rooster

A man owned a casino and invited some friends. It was a dark stormy night, and they all placed their money on the table right before the lights went out. When the lights came back on, the money was gone. The owner put a rooster in an old rusty tea kettle. He told everyone to get in line and touch the kettle after he turned the lights off, and the rooster will crow when the robber touched it. After everyone touched it, the rooster didn't crow, so the man told everyone to hold out their hands. After examining all the hands, he pointed out who the robber was. How did he know who stole the money?
Because the tea kettle was rusty, whoever touched it would have rust on their hands. The robber didn't touch the kettle, therefore he was the only one whose hands weren't rusty.
94.36 %
45 votes