For this case we must find the value of "x" that meets the following equation:

We subtract
on both sides of the equation:

We simplify:

Finally, 
Answer:

First: Figure out the cost per candy bar currently by dividing 3.22 and 14
3.22 / 14 = 0.23
Second: Add in 0.15 to your total to solve for the prior cost of the candy
0.23+0.15 = $0.38
The answer for this problem is b
A.) The insurance company's payment is 80% of the total minus the $500 deductible, so:
(12500 - 500) * .8 = 9600
B.) To find the Copay, you do almost the same thing:
(12500 - 500) * .2 = 2500
C.) Mary's Total Cost: 2500 + 500 = 3000.00