Answer:
$1.25
Step-by-step explanation:
Let  equal the flat rate.
 equal the flat rate.
Let  equal the one-time membership processing fee.
 equal the one-time membership processing fee.
Start with a system of equations:


Use the elimination method and multiply your second equation by  to cancel out the
 to cancel out the  s:
s:

Now combine the equations:


Subtract:

Divide by the coefficient of  , which is
, which is  (I rearranged the equation):
 (I rearranged the equation):

~
Even though we're not solving for the one-time processing fee, to check our work, we'll need to solve for  , so start with the initial system of equations:
, so start with the initial system of equations:


Use the elimination method and multiply the first equation by  , and the second equation by
, and the second equation by  :
:


Multiply:


Subtract:

Divide by the coefficient of  , which is
, which is  (Rearranged equation):
 (Rearranged equation):

~
Check your work:


Solve:


It's correct!