Due to the airline industry charging more fees, the percentage of revenue from fares was only 71% in 2010, and it decreased by 0.8 percentage point per year until 2014 (Source: Bureau of Transportation Statistics). Let p be the percentage of revenue from fares at t years since 2010.
a. Find an equation of a linear model to describe the situation.
b. Use the equation you found in part (a) to estimate in which year 68.5% of revenue came from fares.
c. Solve the equation you found in part (a) for t.
d. Use the equation you found in part (c) to estimate in which year 68.5% of revenue came from fares.
e. Compare the results you found in parts (b) and (d). Which equation was easier to use? Explain.