I am an odd number. Take away a letter and I become even. What number am I?

Replace the question mark with the number below given a simple math problem.

A thief is convicted in Mexico. He gets the death penalty. The judge allows him to say the last sentence to determine how the penalty will be carried out. If the thief lies, he will be hanged, if he speaks the truth he will be beheaded. The thief tells the last sentence and to everybody's surprise some minutes later he is set free because the judge cannot determine his penalty. What did the thief say?

Our product and our sum always give the same answer. Who are we?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

I have branches, but no fruit, trunk or leaves. What am I?

A blonde put eyeliner on her head. Why?

Three people are in a room. Ronni looks at the Nile. The Nile looks at Senthil. Ronni is married but Senthil is not married. At any point, is a married person looking at an unmarried person? Yes, No or Cannot be determined.

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

What is 3/7 chicken, 2/3 cat and 2/4 goat?