A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

What has many keys but can’t open a single lock?

Count The number of F's in the paragraph below:

"FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS"

This is a most unusual paragraph. How quickly can you find out what is so unusual about it? It looks so ordinary, you'd think nothing was wrong with it. Actually, nothing IS wrong with it. But it is not as ordinary as you might think. If you think about it for a bit, you will find out why it is truly so unusual. So what is it? What is so unordinary about this paragraph?

O_er_t_o_

Complete the missing letters of the given word.

What is the riddle which can be asked all day with a different correct answer each time.

A man calls his dog from the opposite side of a river. The dog crosses the river without a bridge or a boat and manages to not get wet. How is this possible?

How many letters are in the alphabet?