Question

Sheleah and her family are planning a trip from Los Angeles, California to Melbourne, Australia. While booking her family's plane tickets, she notices on the itinerary that the airline is offering a sixteen hour straight flight from Los Angeles to Melbourne on a Boeing 747-8 Intercontinental Jet. In an effort to learn more about the capabilities of the Jet, Sheleah does a little research and stumbles upon the following graph and facts about the Jet's fuel consumption.



The Boeing 747-8 Intercontinental Jet can carry approximately 63,500 gallons of jet fuel, making it possible for the jet to travel 14,430 kilometers before needing to refuel.

Use a linear model to predict the amount of jet fuel that is present on the Jet after it has been in flight for 18 hours without stopping to refuel. In two or more complete sentences, explain your answer.




WRITER

Answer 1

Let t be time in hours and F(t) the gallons of fuel remaining. A full tank (63,500 gal) lasts 16 hours, so a linear model is
F(t) = 63,500 − (63,500/16)·t = 63,500 − 3,968.75·t.
Plugging in t = 18 gives F(18) = 63,500 − 3,968.75·18 = −7,937.5 gallons. Since negative fuel is impossible, the plane would have run out of fuel by 16 hours; after 18 hours there would be 0 gallons remaining.