Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

On a beautiful Sunday morning, You ordered a hot tea to your hotel room and suddenly you remember an important thing that needed to be done right now will take around 3 minutes to complete.
Like most people you like your tea to be hot while drinking so, when should you pour cream in the tea?
1. straight away
2. Just people, you drink the team
3. Its does not matter

In a competitive exam, each correct answer could win you 10 points and each wrong answer could lose you 5 points. You sat in the exam and answered all the 20 questions, which were given in the exam.
When you checked the result, you scored 125 marks on the test.

Can you calculate how many answers given by you were wrong?

The square root of number 121 is "11". What is the square root of the number "12345678987654321."?

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

Imagine you are in a room with no windows or doors. How will you get out?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

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

I cry without having a voice.
I fly without having wings.
I bite without having teeth.
I whisper without a mouth.

Who am I?

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.