A man in a car saw a Golden Door, Silver Door and a Bronze Door. What door did he open first?

How can you make number one disappear by adding something to it?

John speaks the truth only once a day in a week. Below are a few hints for you:

First: Days are Sunday, Monday and so on.
Second: One day he says, "I lie on Monday and Tuesday".
Third: On the next day, he says, "Today is either Thursday, Saturday or Sunday".
Fourth: On the next day, he says, "I lie on Wednesday and Friday".

Can you identify the day on which he speaks the truth?

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?

By using 'because' continuously three times, can you make an English statement ?

Only one colour, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

While preparing the table for dinner, wife came up with an idea to tease his mathematician husband. She asked her husband to pick nine toothpicks and make ten without breaking any toothpick.

The husband was also smart and did it within seconds. How ?

If you're 8 feet away from a door and with each move you advance half the distance to the door. How many moves will it take to reach the door?

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