What begins with T, ends with T, and has T in it?

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

You and your two friends are working in a multinational company. How can you three find out the average salary of you all without disclosing your own salary to the other two?

Two friends were betting. One said to the other, "The coin will be flipped twenty times and each time the coin lands on the head, I will give you $2 and each time it lands on the tale, you will give me $3." After flipping the coin twenty times not a single penny was exchanged among them.

How many times did the coin land on heads?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

Prove that the below maths equation is true.

8 + 8 = 91

There was a strange boy who was born before his father. How can this be possible?

I was speeding and ran through a stop sign, yet two traffic officers who were there do nothing about it.

why?

What number divided by 4 is the same as that number minus 4?

Can you calculate the probability of getting a sum of six when a dice is thrown twice?