What's the only room from which no one can enter or leave

Two guards were guarding the camp.Guard-1 was looking towards the south to make sure no threat is coming from the road.Guard-2 was looking at the north to make sure no threat is coming from the top. Suddenly Guard-1 ask the Guard-2 why he is smiling?How Guard-1 knows that Guard-2 is smiling?

Where do fish keep their money?

Jack have ten pairs of black socks, eight pairs of white socks and seven pairs of green socks. Everything is mixed in a draw. As there is no light he were not able to identify the colour of the socks. How many of the socks did he want to take to match one pair

At Delhi Cricket Clubhouse, there were four kids(Kohli, Yuvraj, Pant, and Dhoni) ages 1,2,3 and 4 and have 1,2,3 and 4 cricket balls in different orders.

We know the following facts:

Kohli has more cricket balls than his age.
Dhoni is older than Yuvraj.
One child has the same number of cricket balls as his age.
Pant has fewer cricket balls than Dhoni.
A child aged 3 has two cricket-balls.

Pant is the youngest.

Can you determine the age of the children and the number of cricket balls they have?

Why do Chinese men eat more rice than Japanese men do ?

There are nine dots in the picture that has been attached with this question. Can you join all the dots by drawing four straight lines without picking up your pen?

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

What can go up a chimney down, but can’t go down a chimney up?

Remove two matchsticks to make the below equation correct.