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

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

A large container is kept in open under the rain. Every passing hour, the water collected inside the container becomes double what it was.

In ten hours, the container is filled completely. Can you calculate how long would it have taken to be filled in half?

Lifeless eyes on my smiling face and watch your child's sleeping place. In their dreams they hold me tight. What am I?

Two friends were betting. One said to the other, "The coin will be flipped twenty times and each time the coin lands on the head, I will give you $2 and each time it lands on the tale, you will give me $3." After flipping the coin twenty times not a single penny was exchanged among them.

How many times did the coin land on heads?

They are three errirs in this question. Can you find them?

Can you find out the remainder when 3^300 is divided by 5?

How many triangles can you find in this given picture?

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

In a stable, there are men and horses. In all, there are 22 heads and 72 feet. How many men and how many horses are in the stable