If eleven plus two equals one, what does nine plus five equal?

My cousin lives in one story house in Antarctica. His house is made the of-of sandstone. what is the color of stairs?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

How can a man go eight days without sleep?

Can you name any English verb that becomes its past tense by simply rearranging the alphabets ?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?

After undergoing a successful eye operation, A blind girl has just boarded a train to her home. The doctor asked her to open the bandages after 3 hours. On her train journey, she opened the bandages and within a fraction of the time she commits suicide by jumping off the train.

Though her operation was successful, Why did she commit suicide?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

A mile-long train is moving at sixty miles an hour when it reaches a mile-long tunnel. How long does it take the entire train to pass through the tunnel?

Why do we preferably have round manhole covers and not square ones?