The Prime Number Riddle
Two hundred people in an auditorium are asked to think of a single digit number from 1 to 9 inclusive and write it down. All those who wrote down a prime number are now asked to leave. Ninety people remain behind in the hall. How many of these are expected to have written down an odd number?
Hint: Remember that 1 is not a prime number.
Those that remain behind must have written {1,4,6,8,9} and from this only {1,9} are odd. The probability of an odd number is thus 2/5.
Expected number of odds is 2/5 * 90 = 36 Did you answer this riddle correctly?
YES NO
Expected number of odds is 2/5 * 90 = 36 Did you answer this riddle correctly?
YES NO
Age Of Three Daughters Riddles
I was visiting a friend one evening and remembered that he had three daughters. I asked him how old they were. The product of their ages is 72, he answered. Quizzically, I asked, Is there anything else you can tell me? Yes, he replied, the sum of their ages is equal to the number of my house. I stepped outside to see what the house number was. Upon returning inside, I said to my host, Im sorry, but I still cant figure out their ages. He responded apologetically, Im sorry, I forgot to mention that my oldest daughter likes strawberry shortcake. With this information, I was able to determine all three of their ages. How old is each daughter?
Hint:
3, 3, and 8. The only groups of 3 factors of 72 to have non-unique sums are 2 6 6 and 3 3 8 (with a sum of 14). The rest have unique sums:
2 + 2 + 18 = 22
2 + 3 + 12 = 18
2 + 4 + 9 = 15
3 + 4 + 6 = 13
The house number alone would have identified any of these groups. Since more information was required, we know the sum left the answer unknown. The presence of a single oldest child eliminates 2 6 6, leaving 3 3 8 as the only possible answer. Did you answer this riddle correctly?
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2 + 2 + 18 = 22
2 + 3 + 12 = 18
2 + 4 + 9 = 15
3 + 4 + 6 = 13
The house number alone would have identified any of these groups. Since more information was required, we know the sum left the answer unknown. The presence of a single oldest child eliminates 2 6 6, leaving 3 3 8 as the only possible answer. Did you answer this riddle correctly?
YES NO
Who Stole The $100,000 Riddle
A man leaves a $100,000 dollar bill on his desk and leaves work. When he returns the money is gone. He has three suspects: the cook, the cleaning lady, and the mail guy. The cook says he put the money under a book on his desk to keep it safe. They check and it is no longer there. The maid says she moved it when she was cleaning to the inside of the book between page 1 and 2. They open the book and look between page number 1 and 2 but it isn't there. The mail guy says he saw it sticking out of the book and to keep it safe he moved it to between page number 2 and 3. Once they are done the culprit is promptly arrested. Who did it and how did he know?
Hint:
The mail guy did it because if he checked between page numbers 1 and 2 page numbers 2 and 3 are opposite sides of one page and could not hold the dollar bill. Did you answer this riddle correctly?
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How Old Could He Be?
In 1940, a correspondent proposed the following question:
A man's age at death was one twenty-ninth of the year of his birth. How old was he in 1900?
A man's age at death was one twenty-ninth of the year of his birth. How old was he in 1900?
Hint:
He was 44 years old.
From the question you know the man died between 1900 and 1940. We also know his age at death (x) is one twenty-ninth of the year of his birth (29x). If you add his age at death to the year he was born you get the year he died (30x). Only one year between 1900 and 1940 is divisible by 30, 1920 (the year he died). The year he was born can now be found: 1920 * (29/30) = 1856. So in 1900 he was (1900 - 1856) = 44 years old. Did you answer this riddle correctly?
YES NO
From the question you know the man died between 1900 and 1940. We also know his age at death (x) is one twenty-ninth of the year of his birth (29x). If you add his age at death to the year he was born you get the year he died (30x). Only one year between 1900 and 1940 is divisible by 30, 1920 (the year he died). The year he was born can now be found: 1920 * (29/30) = 1856. So in 1900 he was (1900 - 1856) = 44 years old. Did you answer this riddle correctly?
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I Supply The Facts
I supply the facts, but you supply the thoughts. I am also used to describe realistic droughts. My inhabitants are abstract as their places, And I provide details of their words & faces. I hold details in a very complex form, I may cause your mind to conjure up a storm. I hold many different views from different eyes, My facts can be hard to find; as if in disguise. I may tell of facts, but it may be theories I contain, I can inform, persuade, and can even entertain. I tell of a little girl, and of men chasing a whale, and only through me can you find the answer to this tale. What am I?
Hint: I am educational.
The Iced Tea
Two girls ate dinner together. They both ordered iced tea. One girl drank them very fast and had finished five in the time it took the other to drink just one. The girl who drank one died while the other survived. All of the drinks were poisoned. How did the girl who drank the most survive?The judge dismissed the case. Why?
Hint:
The poison was in the ice. When the girl drank the iced tea, the ice was still fully frozen. Gradually, as the ice cubes melted the poison was released into the drink. Did you answer this riddle correctly?
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Twins Riddle
Hint:
Who Are The Killers?
A very famous chemist was found murdered in his kitchen today. The police have narrowed it down to six suspects. They know it was a two man job. Their names: Felice, Maxwell, Archibald, Nicolas, Jordan, and Xavier.
A note was also found with the body: '26-3-58/28-27-57-16'.
Who are the killers?
A note was also found with the body: '26-3-58/28-27-57-16'.
Who are the killers?
Hint: The numbers have scientific meaning.
Felice and Nicholas are the murderers. The numbers correspond to atomic numbers on the periodic table of elements: 'Fe-Li-Ce/Ni-Co-La-S'. Did you answer this riddle correctly?
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The Red Hat
Once upon a time there lived a king who wished to find the wisest man in the realm to be his assistant. He summons the 3 known wisest men to his court and he administers the following test.
He sits them in a circle, facing each other and he says Im going to put either a red hat or a white hat on each of your heads. He proceeds to place a red hat on each of their heads. Obviously they can see each other but there are no mirrors in the room so they cant see whats on their heads. He says If you can see a red hat, raise your hand. They all raise their hands. Then he says If you can tell what color hat you have on, stand up.
Time goes on, one guy looks at another guy, he looks at the other guy. The other guy looks at him. Finally one guy stands up. The question is how did he know he was wearing a red hat?
He sits them in a circle, facing each other and he says Im going to put either a red hat or a white hat on each of your heads. He proceeds to place a red hat on each of their heads. Obviously they can see each other but there are no mirrors in the room so they cant see whats on their heads. He says If you can see a red hat, raise your hand. They all raise their hands. Then he says If you can tell what color hat you have on, stand up.
Time goes on, one guy looks at another guy, he looks at the other guy. The other guy looks at him. Finally one guy stands up. The question is how did he know he was wearing a red hat?
Hint: For a moment or two, nobody moved. Nobody knew for certain what color his hat was, and thats what told the wisest guy that all of the hats were red.
Step 1:
Wiseguy #1 knows he can see two red hats.
Step 2:
Wiseguy #1 thinks, "Hey, if I were wearing a white hat, Wiseguy #2 would see one red hat and one white."
Step 3:
Wiseguy #1 then thinks, "If I were wearing a white hat, and Wiseguy #2 saw one red hat and one white (and if he were wearing a white hat himself), then Wiseguy #3 would have seen two white hats. So, Wiseguy #3 wouldnt have raised his hand to the first question.
Wiseguy #1 thinks, "If that were true, Wiseguy #2 would be sure that he had a red hat. But since Wiseguy #2 was actually unsure about his hat color, it can only mean one thing, my hat is red." Did you answer this riddle correctly?
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Wiseguy #1 knows he can see two red hats.
Step 2:
Wiseguy #1 thinks, "Hey, if I were wearing a white hat, Wiseguy #2 would see one red hat and one white."
Step 3:
Wiseguy #1 then thinks, "If I were wearing a white hat, and Wiseguy #2 saw one red hat and one white (and if he were wearing a white hat himself), then Wiseguy #3 would have seen two white hats. So, Wiseguy #3 wouldnt have raised his hand to the first question.
Wiseguy #1 thinks, "If that were true, Wiseguy #2 would be sure that he had a red hat. But since Wiseguy #2 was actually unsure about his hat color, it can only mean one thing, my hat is red." Did you answer this riddle correctly?
YES NO
The Savage Sister Riddle
A woman has incontrovertible proof in court that her husband was murdered by her sister. The judge declares, "This is the strangest case I've ever seen. Though it's a cut-and-dried case, this woman cannot be punished."
Hint:
Making Faces Riddle
When asked what he does all day, a man answered that he sits and makes faces. What does he really mean?
Hint:
Not In A Girl's Dress Riddle
Hint:
Floor Math Riddle
Hint:
A Girl's Fave Word
Can you solve this riddle puzzle below using the 3 pictures provided? What do these 2 girls holding hands, this logo and the tattoo all in common?
Boys are unnerved on the mention of it
Once love finds its accompaniment
It becomes a lifelong event.
What is it?
Hint: It's something permanent.
Oil Smuggling Riddle
A detective who was mere days away from cracking an international oil smuggling ring has suddenly gone missing. While inspecting his last-known location, officers find a note: 710 57735 34 5508 51 7718. Currently there are 3 suspects: Bill, John, and Todd. Can you break the detectives code and find the criminal's name?
Hint:
Bill is the suspect, if read upside down the numbers read "Bill is boss. He sells oil." Did you answer this riddle correctly?
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