Kenneth S. answered 06/20/18
Tutor
New to Wyzant
reduction of a price by 0.5 for every year would be simply subtraction of fifty cents per year (age) of truck. Not believable.
Possibly you meant that the price should be HALVED for each year.
Similarly, the 0.2 amount should be expressed more correctly, I believe--namely multiply by 0.8t for t thousands of miles on the odometer.
Please re-think the question and make appropriate revision(s).