Three Rivers Riddle
There are three rivers and after each river lies a grave. A man wants to leave the same number of flowers at each grave and be left with none at the end. However, each time he passes through a river, the number of flowers he has doubles. How many flowers does he have to start with so that he is left with none at the end? And how many does he leave at each grave?
Hint:
This problem has an infinite number of solutions modeled by the equation 8a=7n, where a is the amount of flowers the man starts with and n is the number of flowers he leaves at each grave. The simplest and possibly trivial solution would be to start with 0 flowers and leave 0 flowers at each grave. A more significant solution would be to start with 7 flowers and leave 8 at each grave. Any positive integer multiple of this solution also satisfies the conditions. For example, the man starts with 14 flowers and leaves 16 at each grave; so, 14 doubles to 28, and 28-16= 12; 12 doubles to 24, and 24-16= 8; 8 doubles to 16, and 16-16= 0. The result is the same if the man starts with 21 flowers and leaves 24 flowers at each grave, or starts with 28 and leaves 32. Did you answer this riddle correctly?
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YES NO
Wall Clock Riddle
My only timepiece is a wall clock. One day I forgot to wind it and it stopped. I went to visit a friend whose watch is always correct, stayed awhile, and returned home. There I made a simple calculation and set the clock right. How did I do this when I had no watch on me to tell how long it took me to return home from my friends house?
Hint:
Before I left, I wound the wall clock. When I returned, the change in time it showed equaled the time it took to go to my friend's and return, plus the time I spent there. But I knew the latter, because I looked at my friend's watch both when I arrived and when I left. Subtracting the time of the visit from the time I was absent from my house, and dividing by 2, I obtained the time it took me to return home. I added this time to the time my friend's watch showed when I left, and set this sum on my wall clock. Did you answer this riddle correctly?
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YES NO
Burns Me There Riddle
Hint:
Rearrange the letters of BURN ME THERE and they spell out the words THREE NUMBERS! Did you answer this riddle correctly?
YES NO
YES NO
Pounds Of Sugar Riddle
The grocer had ten customers, each wanting to buy a 2 pound bag of sugar. A 20 pound bag of sugar had been delivered that morning, but he had not yet divided it because he could only find the 5lb and 9lb weights. One of the customers, getting impatient, showed him the quickest way to measure the sugar with the two weights he already had. How did he do it?
Hint:
Weigh out 4 pounds of sugar with the 5lb and the 9lb weights in different pans of the scales. With the 4lb weight , weigh three more lots of 4 pounds each - the remaining sugar will also weigh 4 pounds. Divide each 4 pound portion equally on the two sides of the scales. Did you answer this riddle correctly?
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YES NO
Killed Her Own Sister Riddle
A woman killed her own sister. During the interrogation, she told a story that she had just attended her own mother's funeral a few days before the crime took place. While at the funeral, she said that she met a guy whom she did not know. She thought this guy was amazing, so much her dream guy that she believed him to be just that! She fell in love with him right there, but never asked for his number and could not find him. A few days later, she killed her sister.
Although this woman has confessed to the crime, police are still intrigued by the story, especially because she won't tell them her motive. Hearing this tragic story, with his psychological education background, Detective Thompson easily guessed the woman's motive.
Why did the woman killed her own sister?
Although this woman has confessed to the crime, police are still intrigued by the story, especially because she won't tell them her motive. Hearing this tragic story, with his psychological education background, Detective Thompson easily guessed the woman's motive.
Why did the woman killed her own sister?
Hint:
She was hoping that the guy would appear at the funeral again. Did you answer this riddle correctly?
YES NO
YES NO
Construction Site Murder Riddle
A workman was killed at a construction site. The police began questioning a number of the other fellow workers. Based on past scrapes with the law, many of the following workers were considered prime suspects:
* The electrician was suspected of wiretapping once but was never charged.
* The carpenter thought he was a stud. He tried to frame another man one time.
* The glazier went to great panes to conceal his past. He still claims that he didnt do anything, that he was framed.
* The painter had a brush with the law several years ago.
* The heating, ventilation and air conditioning contractor was known to pack heat. He was arrested once but duct the charges.
* The mason was a prime suspect because he gets stoned regularly.
* The cabinet maker is an accomplished counter fitter.
The autopsy led the police to arrest the carpenter, who subsequently confessed. Why?
* The electrician was suspected of wiretapping once but was never charged.
* The carpenter thought he was a stud. He tried to frame another man one time.
* The glazier went to great panes to conceal his past. He still claims that he didnt do anything, that he was framed.
* The painter had a brush with the law several years ago.
* The heating, ventilation and air conditioning contractor was known to pack heat. He was arrested once but duct the charges.
* The mason was a prime suspect because he gets stoned regularly.
* The cabinet maker is an accomplished counter fitter.
The autopsy led the police to arrest the carpenter, who subsequently confessed. Why?
Hint:
The evidence against him was irrefutable. It was found that the workman, when he died, was hammered. Did you answer this riddle correctly?
YES NO
YES NO
Finding Anna's Picture Riddle
Once upon a time there was a beautiful princess named Anna. Anna's father, the King, wanted to be sure his daughter married an intelligent man. To test his daughter's suitors the King hid Anna's picture in one of three boxes. The suitor had to be able to select the box with Anna's picture on one try and within twenty seconds. On the gold box was the message "Anna's picture is in this box". The silver box had the message "Anna's picture is not in this box." "Anna's picture is not in the gold box" was written on the bronze box. The King would tell each suitor "Only one of the three messages is correct." Which box contained Anna's picture?
Hint:
The silver box contained Anna's picture. If her picture had been in the gold box, two statements would have been true. (The messages on both the gold box and the silver box.) If her picture had been in the bronze box, two statements would have been true. (The messages on the bronze box and the silver box.) Did you answer this riddle correctly?
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YES NO
Adding Eights Riddle
Hint:
Coins In My Wallet Riddle
I have 100 coins in my wallet.
What is the minimum number of coin(s), I would be required in order to make sure each coin touched exactly three other coins.
What is the minimum number of coin(s), I would be required in order to make sure each coin touched exactly three other coins.
Hint:
4
3 placed flat on the table in a triangle(touching each other) and put the fourth one on top of them in the middle. Did you answer this riddle correctly?
YES NO
3 placed flat on the table in a triangle(touching each other) and put the fourth one on top of them in the middle. Did you answer this riddle correctly?
YES NO
Boxes Of Balls Riddle
The first box has two white balls. The second box has two black balls. The third box has a white and a black ball.
Boxes are labeled but all labels are wrong!
You are allowed to open one box, pick one ball at random, see its color and put it back into the box, without seeing the color of the other ball.
How many such operations are necessary to correctly label the boxes?
Boxes are labeled but all labels are wrong!
You are allowed to open one box, pick one ball at random, see its color and put it back into the box, without seeing the color of the other ball.
How many such operations are necessary to correctly label the boxes?
Hint:
Just One!
Because we know all labels are wrong.
So the BW box must be either BB or WW. Selecting one ball from BW will let you know which.
And the other two boxes can then be worked out logically. Did you answer this riddle correctly?
YES NO
Because we know all labels are wrong.
So the BW box must be either BB or WW. Selecting one ball from BW will let you know which.
And the other two boxes can then be worked out logically. Did you answer this riddle correctly?
YES NO
Grapeland To Applecity
You have to send 3,000 grapes 1,000 kilometers from grapecity to appleland. Your truck can carry 1,000 grapes at a time. Every time you travel a kilometer towards appleland you must pay a tax of 1 grape but you pay nothing when going in the other direction (towards grapecity).
What is highest number of grapes you can get to appleland?
What is highest number of grapes you can get to appleland?
Hint:
Step one: First you want to make 3 trips of 1,000 grapes 333 kilometers. You will be left with 2,001 grapes and 667 kilometers to go.
Step two: Next you want to take 2 trips of 1,000 grapes 500 kilometers. You will be left with 1,000 grapes and 167 kilometers to go (you have to leave a grape behind).
Step three: Finally, you travel the last 167 kilometers with one load of 1,000 grapes and are left with 833 grapes in appleland. Did you answer this riddle correctly?
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Step two: Next you want to take 2 trips of 1,000 grapes 500 kilometers. You will be left with 1,000 grapes and 167 kilometers to go (you have to leave a grape behind).
Step three: Finally, you travel the last 167 kilometers with one load of 1,000 grapes and are left with 833 grapes in appleland. Did you answer this riddle correctly?
YES NO
A Pack Of 40 Cards
A pack of cards has 40 cards. You are blindfolded. Out of 40, 25 cards are facing down while 15 are facing up. You have been asked to divide this pack of cards into two decks - so that each deck contains an equal number of face up cards. Remember, you are blindfolded.
How will you do it?
How will you do it?
Hint:
Create a new deck of the exactly same number of cards as are face up cards in the original deck.Take 15 number of cards in a new deck and change their face direction. For example- You create a new deck of 15 cards and out of 15, 5 faces up in a new deck. So remaining 10 faces up are in the old deck. But hey! while creating the new deck you reversed the face direction of new cards. So actually the 5 cards which were facing up are actually face down in the new deck while 10 faces up. Did you answer this riddle correctly?
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YES NO
Captured By The Riddler
In the land of Geopolizza, three men were captured by the infamous Riddler. So, the Riddler buries the three men, named 1, 2 and 3 in such a manner, that 1 is in the front, 2 in the middle and 3 in the back. They are buried neck deep, and cannot move, not even their heads. He shows them 5 caps, two of which are red and 3 of them are white. He then switches off the lights and places a hat on top of their heads. The situation is such that no one can see their hat color, 1 is facing the wall and cant say anything, 2 can see 1 and 3 can see both 1 and 2. Then he tells the rules of his game: "If either of you three can tell the correct color of your head, I will let all of you go. However, if any of you answer wrong, all 3 of you will instantly die. Time is 3 minutes."
Upon 2 and half minutes passing, A shouts the answer and all 3 are released free. How did he know the correct answer ?
Upon 2 and half minutes passing, A shouts the answer and all 3 are released free. How did he know the correct answer ?
Hint:
P3 can only be certain of his cap if 1 & 2 are both white. Since he is not certain then 1 & 2 must be either white/red or red/red. 2 knows this but the only combination that he will be able to know the colour of his own cap is if he sees that 1 is wearing a white cap. 1 knows this but as 2 remains uncertain then 1 must be wearing a red cap. Did you answer this riddle correctly?
YES NO
YES NO
Accepting The Bet Riddle
There is a box in which distinct numbered balls have been kept. You have to pick two balls randomly from the lot.
If someone is offering you a 2 to 1 odds that the numbers will be relatively prime, for example
If the balls you picked had the numbers 6 and 13, you lose $1.
If the balls you picked had the numbers 5 and 25, you win $2.
Will you accept that bet?
If someone is offering you a 2 to 1 odds that the numbers will be relatively prime, for example
If the balls you picked had the numbers 6 and 13, you lose $1.
If the balls you picked had the numbers 5 and 25, you win $2.
Will you accept that bet?
Hint:
Yes, you should accept the bet. Simply because the odds of picking two relatively prime numbers are 60%. It is a win-win situation for you if you keep playing. Did you answer this riddle correctly?
YES NO
YES NO
A Special Integer Riddle
A special integer exists in mathematics that shows a special property. If you subtract any number from that integer, the result will always be divisible by the successor of that number completely.
Do you know what that integer is ?
Do you know what that integer is ?
Hint:
The required integer is -1.
For an example, let us subtract 7 from -1.
-1 - 7 = -8
Now the successor of 7 is 8 and (-8) is exactly divisible by 8.
You can try that for any number and it will hold true. Did you answer this riddle correctly?
YES NO
For an example, let us subtract 7 from -1.
-1 - 7 = -8
Now the successor of 7 is 8 and (-8) is exactly divisible by 8.
You can try that for any number and it will hold true. Did you answer this riddle correctly?
YES NO
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