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

A train full of passengers goes through a tunnel. When the train comes out from the other end, there is no single person on the train.

How did it happen?

Using eight eights and addition only, can you make 1000?

I am a prime number.
The double of myself is equal to the square of me.

which number am I?

What will you call your mother's brother's brother-in-law?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

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?

If you go to the movies and you're paying, is it cheaper to take one friend to the movies twice, or two friends to the movies at the same time?

Jack was having a candle light dinner with his girlfriend. Suddenly a cold gush of wind entered through the open window and three of the ten candles were extinguished. Assuming that none of the other candles were extinguished.

How many candles are they left with in the end ?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?