How many sides does a circle have?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

Your job is to measure 45 minutes if you have only two cords and matches to light the cords.

1. The two cords are twisted from various materials, so their different segments can burn at different rates.
2. Each cord burns from end to end in exactly one hour.

Describe your way of measuring the 45 minutes.

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

This is a most unusual paragraph. How quickly can you find out what is so unusual about it? It looks so ordinary, you'd think nothing was wrong with it. Actually, nothing IS wrong with it. But it is not as ordinary as you might think. If you think about it for a bit, you will find out why it is truly so unusual. So what is it? What is so unordinary about this paragraph?

There are a number of books on a shelf. If one book is the 4th from the left and 6th from the right, how many books are on the shelf?

While going to your grandmother's house, you counted Twenty houses on the right side. While returning back to your home, you counted Twenty houses on the left side.

How many houses are there between your home and your grandmother's home?

What kind of band never plays music?

What have one eye but still cannot see?

Why 1729 is a magic number? Answer Logically.