What's the only room from which no one can enter or leave

If I put in one bird per cage, I have one bird too many. If I put in two bird per cage, I have one cage too many. How many cages and birds do I have?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Count the number of triangles in the below picture?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

In The 1st month of this year(the year 2013), I noticed that the date 13-1-13 (13 January 2013) is special.

This date is special as:

Date * Month = Year.

Can you figure out which year of this century has a maximum number of such dates?

What Deficiency does the below rebus represent?

VIT_MIN

What is so fragile that saying its name breaks it?

Which flower has two lips?

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?