If you say my name, I will no longer exist. What am I?

On a certain island, people are gifted with assorted eye colours. There are a hundred green-coloured and a hundred grey-coloured pairs of eyes. On that island, there is no mirror available. Thus no one knows the eye color of their own. They could have asked each other but that is prohibited. They are not allowed to converse with each other. However, they can study and analyze other's eyes. They don't even know the statistics so it is believable to them that their eyes can be blue as well. There is a chance of freedom from the island. If anyone can guess the colour of his own eyes correctly, he will be set free and can leave the island.

On one particular day, an outsider comes to the island and announces that he has seen someone with grey colour eyes. What will happen now?

Out of three Friends John, Jacob and Jonny one of them is a king, one is a bureaucrat, and one is a Spy.

The king always tells the truth, the bureaucrat always lies, and the Spy can either lie or tell the truth.

John says: Jonny is a bureaucrat
Jacob says: John is a king
Jonny says: I am a Spy

Tell me, Who is the king, who is the bureaucrat, and who is the Spy?

Three ants are going up a hill, one behind the other. The last ant then says to the other ants, 'There is an ant behind me!'' How come?

A mules travels the same distance daily.
I noticed that two of his legs travels 10km and the remaining two travels 12km.
Obviously two mules legs cannot be a 2km ahead of the other 2.

The mules is perfectly normal. So how come this be true ?

Which five letter word can be added at the end of below word to form a
valid word?

> Pin
> Check
> Boiling
> View

The person who makes it has no need for it; the person who buys it has no use for it. The person who uses it can neither see nor feel it. What is it?

Can you solve the below algebraic mathematical equation?

(J+O+I+N+T)3 = JOINT

Rob is taller than Edwin, and Jurgen is shorter than Rob.
Of only one of the following statements, we now certainly know it is correct:

A.Edwin is taller than Jurgen
B.Jurgen is taller than Edwin
C.It cannot be determined if Jurgen or Edwin is the tallest.

A Japanese ship was en route to a mission on foreign seas. The captain of the ship felt tired and thought of taking a bath. He went for taking the shower and removed his diamond ring and Rolex and kept them on the table. When he returned after taking the bath, he found that the ring and watch were stolen.

He called the five members of the crew whom he suspected and asked them what they were doing for the last 15 minutes.

The Italian cook (with a butcher knife in hand): I was in the fridge room getting meat for cooking.

The British Engineer (with a high beam torch in hand): I was working on a generator engine.

The Pakistani seaman: I was on the mast correcting the flag which was upside down by mistake.

The Indian Radio officer: I was trying to make a contact with the company to inform them about our position.

The American navigation officer: I am on night watch, so I was sleeping in my cabin.

Upon listening to them, the captain caught the lying member. Who do you think stole the valuables?