The following table shows the amount spent by four U.S. airlines to fly one available seat 1 mile in the second quarter of 2014.† Set up a system and then solve using technology. HINT [See the...

The following table shows the amount spent by four U.S. airlines to fly one available seat 1 mile in the second quarter of 2014.† Set up a system and then solve using technology. HINT [See the technology note accompanying Example 1.]

Suppose that, on a 3,000-mile New York to Los Angeles flight, United Continental, American, and Southwest flew a total of 240 empty seats, costing them a total of $100,920. If United Continental had three times as many empty seats as American, how many empty seats did each of these three airlines carry on its flight?