You visit a remote desert island inhabited by one hundred very friendly dragons, all of whom have green eyes. They haven’t seen a human for many centuries and are very excited about your visit. They show you around their island and tell you all about their dragon way of life (dragons can talk, of course).
They seem to be quite normal, as far as dragons go, but then you find out something rather odd. They have a rule on the island which states that if a dragon ever finds out that he/she has green eyes, then at precisely midnight on the day of this discovery, he/she must relinquish all dragon powers and transform into a long-tailed sparrow. However, there are no mirrors on the island, and they never talk about eye color, so the dragons have been living in blissful ignorance throughout the ages.
Upon your departure, all the dragons get together to see you off, and in a tearful farewell you thank them for being such hospitable dragons. Then you decide to tell them something that they all already know (for each can see the colors of the eyes of the other dragons). You tell them all that at least one of them has green eyes. Then you leave, not thinking of the consequences (if any). Assuming that the dragons are (of course) infallibly logical, what happens?
If something interesting does happen, what exactly is the new information that you gave the dragons?
Players initially have a 2/3 chance of picking a goat. Those who swap always get the opposite of their original choice, so those who swap have 2/3 chance of winning the car. Players who stick have a 1/3 chance of winning the car. The solution is based on the premise that the host knows which door hides the car and intentionally reveals a goat. If the player selected the door hiding the car (1/3), then both remaining doors hide goats and the host may choose either door at random, and switching doors loses in 1/3. On the other hand, if the player initially selected a door that hides a goat (a 2-in-3 chance), then the host’s choice is no longer at random, as he is forced to show the second goat only, and switching doors wins for sure in 2/3.
Suppose you’re on a game show, and you’re given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what’s behind the doors, opens another door, say No. 3, which has a goat. He then says to you, “Do you want to pick door No. 2?” Is it to your advantage to switch your choice?
They both lied.
The child with the black hair is the girl, and the child with the white hair is the boy.
(If only one lied they would both be boys or both be girls)
A boy and a girl are chatting.
“I am a boy”, said the child with black hair.
“I am a girl”, said the child with white hair.
At least one of them lied. What colour hair does the boy have?
Solution: Derek was the culprit.
Looking at Brian’s statement if it was Charles, then Brian was lying in his first statement, which makes the second statement true. Which would mean that it was both Charles and Alan. So it can’t be Charles.
Which means Derek was lying in his first statement, which makes the second statement true. Therefore it can’t be Alan.
So Eric’s second statement must be false, meaning his first statement was true, therefore it was Derek.
After a local Post Office burglary, five suspects were being interviewed.
Below is a summary of their statements.
Police know that each of them told the truth in one of the statements and lied in the other.
From this information can you tell who committed the crime?
It wasn’t Charles
It was Alan
It was Charles
It wasn’t Alan
It was Brian
It wasn’t Eric
It was Eric
It wasn’t Brian
It was Derek
It was Alan
The correct answer is 13 triangles – the large outer triangle, plus 9 small inner triangles, plus 3 medium size triangles comprised of 3 triangles each.
Culprit Weapon Location
Mrs Red spanner kitchen
Dr Purple rope study
Major Yellow lead piping library
Miss Beige gun conservatory
# Owner Wore Colour
1 Alfred 3 red
2 Alice 2 green
3 Arthur 4 blue
4 Anne 1 yellow