The more of this there is, the less you see. What is it?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

If 1+9+8=1, what is 2+8+9?

You have three orange, two pink and five purple balls in the drawer beside your bed. There is no electricity and the room is entirely dark. How many balls must you take out to ensure at least one ball of each colour at least?

Can you find a number that lies one third of the distance between 1/3 and 2/3?

If eleven plus two equals one, what does nine plus five equal?

You have a square. What you have to do is cut and reassemble the square such that you create a Red Cross sign that has the same volume as that of the square.

I have nine bottles of wine and one of the nine bottles is poisoned.
I need to find the poisoned bottle with two facts
(1) Poison is deadly, only a sip will cost death
(2) I have two mice to do so.

How should I do it?

What 5-letter word typed in all capital letters can be read the same upside down?

A man is lying dead in a field where no one is around. His head is split open and his legs are disfigured. Near to him, there is an unopened package. No living organism can be found anywhere at the crime scene.

How did he die?