Riddle #967

logic

Prisoner sentenced to death

You are a prisoner sentenced to death. The Emperor offers you a chance to live by playing a simple game. He gives you 50 black marbles, 50 white marbles and 2 empty bowls. He then says, "Divide these 100 marbles into these 2 bowls. You can divide them any way you like as long as you use all the marbles. Then I will blindfold you and mix the bowls around. You then can choose one bowl and remove ONE marble. If the marble is WHITE you will live, but if the marble is BLACK... you will die." How do you divide the marbles up so that you have the greatest probability of choosing a WHITE marble? HINT: The answer does not guarantee 100% you will chose a white marble, but you have a much better chance.
Place 1 white marble in the bowl, and place the rest of the marbles in the other bowl (49 whites, and 50 blacks). This way you begin a 50/50 chance of choosing the bowl with just one white marble, therefore life! BUT even if you choose the other bowl, you still have almost a 50/50 chance at picking one of the 49 white marbles.
90.47 %
44 votes

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logic

Miraculously unhurt

Brad starred through the dirty soot-smeared window on the 22nd floor of the office tower. Overcome with depression he slid the window open and jumped through it. It was a sheer drop outside the building to the ground. Miraculously after he landed he was completely unhurt. Since there was nothing to cushion his fall or slow his descent, how could he have survived the fall?
Brad was so sick and tired of window washing, he opened the window and jumped inside.
94.59 %
47 votes

logic

Speedy service station

Shadow drove into the Speedy Service Station and pulled up to the pumps. "Fill it up, please," said Shadow. "This may sound strange," said the owner, "but I'd rather fill two cars from out of town than one car from this town." Shadow looked across the small town and replied, "I know just what you mean." Why would the owner feel this way?
The owner would rather fill two cars from anywhere than one car from town because he would make twice the amount of money.
93.22 %
37 votes

logic

Traveling all over the world

A man named Stewart is traveling all over the world. First he travels to Cape Town in South Africa. Then to Jakarta in Indonesia. Then to Canberra in Australia. Then to Rome in Italy. Then to Panama City in Panama. Where does he travel next?
Santiago in Chile. He travels to each continent in alphabetical order then to the capital of the country that has the most southern latitude.
93.22 %
37 votes

logic

Suitcase Locks

A man needs to send important documents to his friend across the country. He buys a suitcase to put the documents in, but he has a problem: the mail system in his country is very corrupt, and he knows that if he doesn't lock the suitcase, it will be opened by the post office and his documents will be stolen before they reach his friend. There are lock stores across the country that sell locks with keys. The only problem is that if he locks the suitcase, he has no way to send the key to his friend so that the friend will be able to open the lock: if he doesn't send the key, then the friend can't open the lock, and if he puts the key in the suitcase, then the friend won't be able to get to the key. The suitcase is designed so that any number of locks can be put on it, but the man figures that putting more than one lock on the suitcase will only compound the problem. After a few days, however, he figures out how to safely send the documents. He calls his friend who he's sending the documents to and explains the plan. What is the man's plan?
The plan is this: 1. The man will put a lock on the suitcase, keep the key, and send the suitcase to his friend. 2. The friend will then put his own lock on the suitcase as well, keep the key to that lock, and send the suitcase back to the man. 3. The man will use his key to remove his lock from the suitcase, and send it back to the friend. 4. The friend will remove his own lock from the suitcase and get to the documents.
93.39 %
38 votes

logic

Headwaiter in a restaurant

Betty signals to the headwaiter in a restaurant, and says, ''There is a fly in my tea.'' The waiter says ''No problem Madam. I will bring you a fresh cup of tea.'' A few minutes later Betty shouts, ''Get me the manager! This is the same cup of tea.'' How did she know? Hint: The tea is still hot.
Betty had already put sugar in her tea before sending it back. When the "new" cup came, it was already tasted sweet.
93.39 %
38 votes

cleanlogicmathshort

Hards maths number

Create a number using only the digits 4,4,3,3,2,2,1 and 1. So I can only be eight digits. You have to make sure the ones are separated by one digit, the twos are separated by two digits the threes are separated with three digits and the fours are separated by four digits.
41312432.
93.22 %
37 votes

logicmath

In a bank

A women walks into a bank to cash out her check. By mistake the bank teller gives her rupee amount in change, and her paise amount in rupees. On the way home she spends 5 paise, and then suddenly she notices that she has twice the amount of her check. How much was her check amount ?
The check was for Rupees 31.63. The bank teller gave her Rupees 63.31 She spent .05, and then she had Rupees 63.26, which is twice the check. Let x be the rupees of the check, and y be the paise. The check was for 100x + y paise He was given 100y + x paise Also 100y + x - 5 = 2(100x + y) Expanding this out and rearranging, we find: 98y = 199x + 5 or 199x ≡ -5 (mod 98) or 98*2*x + 3x ≡ -5 (mod 98) 3x ≡ -5 ≡ 93 (mod 98) this quickly leads to x = 31
93.84 %
41 votes

logicmath

4 gallon of water

How to measure exactly 4 gallon of water from 3 gallon and 5 gallon jars, given, you have unlimited water supply from a running tap.
Step 1. Fill 3 gallon jar with water. ( 5p – 0, 3p – 3) Step 2. Pour all its water into 5 gallon jar. (5p – 3, 3p – 0) Step 3. Fill 3 gallon jar again. ( 5p – 3, 3p – 3) Step 4. Pour its water into 5 gallon jar untill it is full. Now you will have exactly 1 gallon water remaining in 3 gallon jar. (5p – 5, 3p – 1) Step 5. Empty 5 gallon jar, pour 1 gallon water from 3 gallon jar into it. Now 5 gallon jar has exactly 1 gallon of water. (5p – 1, 3p – 0) Step 6. Fill 3 gallon jar again and pour all its water into 5 gallon jar, thus 5 gallon jar will have exactly 4 gallon of water. (5p – 4, 3p – 0) We are done !
91.39 %
49 votes

logicmystery

Kidnapped kid

A rich man's son was kidnapped. The ransom note told him to bring a valuable diamond to a phone booth in the middle of a public park. Plainclothes police officers surrounded the park, intending to follow the criminal or his messenger. The rich man arrived at the phone booth and followed instructions but the police were powerless to prevent the diamond from leaving the park and reaching the crafty villain. What did he do?
This is a true story from Taiwan. When the rich man reached the phone booth he found a carrier pigeon in a cage. It had a message attached telling the man to put the diamond in a small bag which was around the pigeon's neck and to release the bird. When the man did this the police were powerless to follow the bird as it returned across the city to its owner.
89.25 %
53 votes