Conversation so far:
what happens to the winners of america's got talent
The winner receives a large cash prize, primarily paid over a period of time, and, since the third season, a chance to headline a show on the Las Vegas Strip.
how large is the cash prize to the winners of america's got talent
Although stipulated as $1 million per the program's advertising, in reality winners can choose to either take it as a lump sum, or as a financial annuity of this amount.

Question: how is a winner chosen
Self-contained rewrite: how is a winner chosen on america's got talent