Originally Posted by balonywolf
I would assume it's just so they can "earn" a prize instead of just winning because they entered.
Thats exactly right. and you don't have to answer the question on the spot, at least for lottery tickets it isn't. Normally its elementary school level math, like (1+5)*8/(4-1). Other questions are trivia based, those are normally for media based contests, like TV shows, they are really easy. For example, if you were trying to win a DVD of Transformers the question might be "What 1980's cartoon is the movie Transformers based off of?". Although its sooo much harder for us to win these prizes, the up side is that we don't get taxed on winnings.