Two candles are the same length.
Both are lit at the same time.
The first candle (#1) burns six hours before it extinguishes itself.
The second candle (#2) burns three hours before it extinguishes itself.
During how much time must candle #1 burn before it is twice the length of candle #2?
2 hours
You are on an island and there are three crates of fruit that have washed up in front of you. One crate contains only apples. One crate contains only oranges. The other crate contains both apples and oranges.
Each crate is labeled. One reads "apples", one reads "oranges", and one reads "apples and oranges". You know that NONE of the crates have been labeled correctly - they are all wrong.
If you can only take out and look at just one of the pieces of fruit from just one of the crates, how can you label ALL of the crates correctly?
Take a piece of fruit from the "apples and oranges" crate. If it's an apple then you know that is the "apples" crate since ALL THE CRATES ARE LABLED INCORRECTLY. This means the crate marked "apples" must be "oranges" and the crate marked "oranges" must be "apples and oranges".
What mathematical symbol can be placed between 5 and 9, to get a number greater than 5 and smaller than 9?
Decimal point 5.9
This is a story about three people (A, B a C) crossing a desert. A hated C and decided to kill him - he poisoned the water in his sack (only C had water). B also wanted to kill C (not knowing that the water of C had been already poisoned) and so B made a hole into the sack of C and the water spilt out. A few days later C died of thirst.
Who was the murderer - A or B?
Well, this is a hard one. In my opinion, there is no clear solution. Each point of view is correct, somehow. Most of the people would say that A is the murderer. Solicitor of B would stress 2 things:
1. to take away poisoned water from someone does not mean killing him,
2. B just made C live longer, even if he did not mean to (the poison might have killed C earlier).
However, solicitor of A could present the following argument:
"How can be A be punished for committing a murder by poisoning C, if C did not swallow a single drop of poison."
It is morally clear that both A and B are guilty of homicide attempt. Legally, 2 different courts could judge them in 2 different ways. And logic gives us the opportunity to write a whole book on this topic.
A passenger train leaves New York for Boston traveling at the speed of 80 km/hr. In half an hour a freight train leaves Boston for New York traveling at the speed of 60 km/hr.
Which train will be further from New York when they meet?
Of course, when the trains encounter, they will be approximately the same distance away from New York. The New York train will be closer to New York by approximately one train length because they're coming from different directions. That is, unless you take "meet" to mean "perfectly overlap".
There is a certain crime, that if it is attempted, is punishable, but if it is committed, is not punishable. What is the crime?
A Suicide
A teacher of mathematics used an unconventional method to measure a 15-minute time limit for a test. He just used 7 and 11-minutehourglasses. During the whole time he turned sandglasses only 3 times (turning both hourglasses at once count as one flip).
Explain how the teacher measured 15 minutes.
1. Turn them both over so they start to spill
2. when the 7 min timer is up, turn that one back over. there will be 4 mins left in the 11 min one
3. when the 11 min timer is finished, in the 7 timer it will be 3 mins at the top and 4 at the bottom. You need 4 more mins, so you turn it back over so the 4 mins (in the 7) will spill back.
so it will be the 11 mins (from the 11 timer) and the remainder 4 mins (from the 7 timer)
A man aproaches you in a dark alley. He says, 'If you tell a lie, I will kill you with a knife. If you tell the truth, I will kill you with a gun.'
What do you say to stay alive?
Recognize that only declarative statements have a truth value.
Don't make a declarative statement; that way it won't be the truth or a lie.
Here are three possibilities:
[1] Remain silent. - or if you must say something, ask a question
[2] Why do you want to kill me? - or exclaim something:
[3] No! Please do not kill me!
a boy was at a carnival and went to a booth where a man said to the boy,"If i write your exact weight on the paper u'll pay me $50". If i cannot then I will pay you $50. The boy looked around saw no scale so he agrees, thinking no matter what the man says he'll just say he ways more or less. In the end the boy ends up paying the man $50. How did the man win the bet
The man did exactly what he said. He wrote "YOUR EXACT WEIGHT" on the peice of paper