Complex sentence: A mistake at any point ended the round and lost all accumulated money therein; getting five correct answers won a jackpot that started at $5,000 and went up by that amount each game it went unclaimed.
Split into simpler sentences: A mistake at any point ended the round and lost all accumulated money therein. Getting five correct answers won a jackpot that started at $5,000 and increased by that amount each game it went unclaimed.