How can a man go eight days without sleep?

I left my campsite and hiked south for 3 miles. Then I turned east and hiked for 3 miles. I then turned north and hiked for 3 miles, at which time I came upon a bear inside my tent eating my food! What colour was the bear?

If a wheel has 54 spokes, how many spaces are there between the spokes?

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

What does this Rebus Picture means ?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

You measure my life in hours
I serve you by expiring
I vanish faster when I am thin
and slower when I am thick
The wind is my energy
What am I?

What is wrong in the below Picture?

Christina, Allison and Lena are 3 daughters of John a well-known Mathematician, When I asked John the age of their daughters. He replied "The current age of her daughters is prime. Also, the difference between their ages is also prime."

How old are the daughters?