Which city is three-fifths chick two third cat and 50% goat?

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

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?

I have a big mouth and I am also quite loud! I am NOT a gossip but I do get involved with everyone's dirty business.

You and your two friends are working in a multinational company. How can you three find out the average salary of you all without disclosing your own salary to the other two?

You need to arrange three 7 and mathematical symbols to form number 1?

You can take four of the five letters out of this word, but the pronunciation never changes. What is the word?

There is a square piece of paper with a hole that is denoted by the circle on the top right side in the given picture. You have to cut the paper in a manner that it forms two and only two separate pieces of paper and then rearrange the pieces in a manner that the holes come in the centre of the paper.