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

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

No one wants to have it, but if one got it, he does not want to lose it. What is It?

A deaf and mute man goes to the train station. Tickets for the train are 50 cents each. The man goes to the ticket booth and hands the man inside just a dollar. The man in the booth hands him two tickets.

How did the man in the booth know to give him two tickets without even looking at him?

In a football game, Christina defeated Teresa by 2 - 0 but no man from either side scored. How can this be possible?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

John was driving a bus and got stuck when passing through an underpass. Then came Jacob with a needle and got the bus out of the underpass.

What did the boy do?

What is common among 11, 69, and 88?

What number do you get when you multiply all of the numbers on a telephone's number pad?

What does the following represent?

N N N N N N N

A A A A A A A

C C C C C C C