Why is the longest human nose just 11 inches?

What number when divided in half becomes zero?

Before reading ahead, you must know the fact that only one of the people here is telling the truth.

A says that B is lying.
B says that C is lying.
C says both A and B are lying.

Can you find out who is speaking the truth?

I am white when I am dirty, and black when I am clean. What am I?

Can you complete the sequence?

192, 021, 222, 324, 252, 627, 2__, 9__?

After teaching his class all about Roman numerals (X = 10, IX=9 and so on) the teacher asked his class to draw a single continuous line and turn IX into 6. The teacher's only stipulation was that the pen could not be lifted from the paper until the line was complete.

If two's company, and three's a crowd, then whats four and five ?

It is raining today at 11:59 am. What is the probability of sunny weather after 72 hours?

A quarter is one-fourth of a dollar but Mr. John has changed the equation as below :

DOLLAR * 4 = QUARTER

Can you replace each letter with a digit to make the above solution correct?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?