99 points suppose that the weight (in pounds) of an airplane is a linear function of the amount of fuel (in gallons) in its tank. when carrying 12 gallons of fuel, the airplane weighs 2176 pounds. when carrying 46 gallons of fuel, it weighs 2399 pounds. how much does the airplane weigh if it is carrying 54 gallons of fuel?

Find the difference in gallons and the difference in the weights

46 - 12 = 34 gallons

2399 - 2176 = 223 pounds
 so 34 gallons of gas weighs 223 pounds

find weight per pound: 223 pounds / 34 gallons = 6.5588 pounds per gallon
 round to 6.6 pounds per gallon

54 gallons - 46 gallons = 8 gallons

 8 gallons x 6.6 pounds per gallon = 52.8 pounds, round to 53 pounds

2399 + 53 = 2452 weight of plane with 54 gallons