Can you convert the number zero(0) into a positive number using just one mathematical operator ?

How many bananas can you eat if your stomach is empty?

A boy purchased a book from a bookkeeper and gave him $100.
The cost of the book is $50 but the bookkeeper has no change, so he gets the change from the next shop and returns the boy his $50.

After some time the next shopkeeper came with the $100 note and told the bookkeeper that the note was a fraud, so he took the money back.

How much loss did the bookkeeper face?

That attorney is my brother, testified the accountant.

But the attorney testified he didn't have a brother.

Who is lying?

The following question it puts forth you:

25 - 55 + (85 + 65) = ?

Then, you are told that even though you might think it's wrong, the correct answer is actually 5!

Whats your reaction to it? How can this be true?

In the Mexico City area, there are two Houses H1 and H2. Both H1 and H2 have two children each.
In House H1, The boy plays for Mexico Youth academy and the other child plays baseball.
In House H2, The boy Plays soccer for his school in Mexico and they recently have a newborn.

Can you prove that the probability of House-H1 having a girl child is more than that of House-H2?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

In a jungle where there are no street lights or any other artificial source of lights, I notice a black snake crossing the road.
How did I get sight of the snake?

In a rainy season, one day 3 huge ladies walked under a normal-sized umbrella.
The umbrella is not huge enough to accommodate all 3 ladies yet not a single lady got wet. Why?