Getthere airlines currently charges $200$ dollars per ticket and sells $40{,}000$ tickets a week. for every $10$ dollars they increase the ticket price, they sell $1000$ fewer tickets a week. how many dollars should they charge to maximize their total revenue?
Suppose GetThere Airlines increases their ticket price to $200+10n = 10(20+n)$ dollars. Then the number of tickets they sell is $40,000-1000n = 1000(40-n)$ . Therefore, their total revenue is