What has many keys but can’t open a single lock?

You see a mathematical expression in the picture. Can you think of a movie that this expression refers to?

A man in a car saw a Golden Door, Silver Door and a Bronze Door. What door did he open first?

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

I have some blue and red sock in my drawer. I have a total of 4 socks. I pick 2 socks and the chance that I get a pair of red socks is 1/2.

What is the chance of picking a pair of blue socks?

A kind heart person buy packed food at 3$/packet from United states and sells them at 1$/packet at Africa. After some time he becomes a millionaire.

How come the guy become millionaire ?

Here is what you have to do. You have to throw a ball as hard as you can but it must return back to you even if it does not bounce at anything. Also, you have nothing attached to the ball. There is no one on the other end to catch that ball and throw it back at you.

How will you do it?

In the Mexico City area, there are two Houses H1 and H2. Both H1 and H2 have two children each.
In House H1, The boy plays for Mexico Youth academy and the other child plays baseball.
In House H2, The boy Plays soccer for his school in Mexico and they recently have a newborn.

Can you prove that the probability of House-H1 having a girl child is more than that of House-H2?

Can you name any English verb that becomes its past tense by simply rearranging the alphabets ?

You are given four results as below:
1111 = F
2222 = E
3333 = T
Then, can you find out how to code 4444?