When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

What jumps when it walks and sits when it stands?

A man looks at a painting in a museum and says, “Brothers and sisters I have none, but that man’s father is my father’s son.” Who is in the painting?

Can it be possible to build a house that has all its four walls facing towards the South?

People make me, save me, change me, raise me. What am I?

I never was there, I am always to be.
You have never ever seen me, not ever you will.
Yet I am the confidence of everyone.

Who Am I?

Jenifer and Jesica are having a conversation.

Jenifer: I am definitely not over 30.
Jesica: I am 28 and you are surely 5 years older to me at least.
Jenifer: No, you are at least 29.

You are told that both of them are lying throughout in the conversation. Can you find their respective ages?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day

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.

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?