Suppose we lay down two cups in front of you. One of the cups is filled with tea and the other one with coffee. Now we ask you to take a spoonful of tea and mix it with the coffee. At this moment, the coffee cup has a mixture of tea and coffee. You have to take that mixture (spoonful) and add it back to the tea.

Can you now tell if the cup of coffee has more tea or the cup of tea has more coffee?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

Its something that each of us devours,
Not just us but birds, beats, trees, and flowers,
Frets iron and nibbles steel,
Toil hard stones to meal,
Exterminates king, collapse town,
And blows the mountains down.

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.

A mother bought three dress for her triplets daughters(one for each) and put the dresses in the dark. One by one the girls come and pick a dress.
What is the probability that no girl will choose her own dress?

A man walked into a pub and went straight towards the Barman. He asked for a dirty martini from the Barman. The Barman thought something and then pulled out a pistol from his drawer and aimed it directly at the man. Why did he do that?

What is red and smells like blue paint?

I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?