The Atlanta Braves marketing staff knows it has 20,000 seats in the stadium priced at $20 per ticket, 13,000 priced at $30 per ticket, and 17,000 priced at $50 per ticket. Jim says that the marketing materials should say that average ticket price is $30, Jill says it should be $33, and Fred says it should be $35.20. Who is most correct?