If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

Double it and multiply it by 4. Then divide it by 8 and you’ll have it once more. What number is it?

John is looking at Jenifer, but Jenifer is looking at Jacob. John is married, but Jacob is not.

Is a married person looking at an unmarried person ?

What is a word made up of 4 letters, yet is also made up of 3. Sometimes is written with 9 letters, and then with 4. Rarely consists of 6, and never is written with 5.

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
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?

A prisoner is told: "If you tell a lie, we will hang you and if you tell the truth, we will shoot you." What did the prisoner say to save himself?

A man dies of old age on his 25 birthday. How is this possible?

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

I am quite hot but become too cold if you remove the first two letters. What am I?