The cost of a parking permit consists of a one-time administration fee plus a monthly fee. a permit purchased for 12 months costs $660. a permit purchased for 15 months costs $810. what is the administration fee?
The general equation that may be used to determine the total cost of the parking permit,
P = A + mt
where P is the total cost, A is the administration fee, m is the monthly fee and t is the number of months. Substituting the known values to the equation,
(1) 660 = A + 12m
(2) 810 = A + 15 m
Solving for the solutions of the equation gives A = 60 and m = 50. Thus, the administration fee is $60.
let
x--------> the monthly fee
y--------> the administration fee
we know that
\(660=y+12x\) --------> equation \(1\)
\(810=y+15x\) --------> equation \(2\)
Multiply by \(-1\) equation \(1\)
\(-660=-y-12x\) ------> equation \(3\)
Adds equation \(2\) and equation \(3\)
\(810=y+15x\\-660=-y-12x\\---------\\ 810-660=15x-12x\\ 3x=150\\ x=50\ dollars\)
Find the value of y
\(660=y+12x\\ 660=y+12*50\\ y=660-600\\ y=60\ dollars\)
therefore
the answer is
the administration fee is equal to \(60\ dollars\)