A mules travels the same distance daily.
I noticed that two of his legs travels 10km and the remaining two travels 12km.
Obviously two mules legs cannot be a 2km ahead of the other 2.

The mules is perfectly normal. So how come this be true ?

How do you go from 98 to 720 using just one letter?

See the given image carefully. What you have to do is move the blue checkers in the position of the black checkers and vice versa. You are only allowed to move the checker to an adjacent empty space. Do it in the least possible moves.

What does this Rebus Picture means ?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

Sherlock Holmes was challenged to make a pre-drawn line smaller without erasing it. He did it in fractions of seconds. How?

Riddle me this, Riddle me that,
What am I? I am made of wood, but you can't see me down?

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

What is 3/7 chicken, 2/3 cat and 2/4 goat?

Why blonde cannot dial 911?