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

I’m tall when I’m young, and I’m short when I’m old. What am I?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

I am beautiful, up in the sky. I am magical, yet I cannot fly. To people I bring luck, and to some people, riches. The boy at my end does whatever he wishes. What am I?

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?

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

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

During which month do people sleep the least?

How many times can you subtract the number two from the number fifty?