Easy
Math and Logic
Pick 1 of 1000 seats. 990 empty removed. Odds now?
Choose an answer
A.1/10
B.1/2
C.1/100
D.1/1,000
Answer: 1/1,000
Removing empty seats you didn't pick doesn't change the fact that you had a 1-in-1000 chance at the start. The prize is still where it was (or wasn't).