insurance and copayments: how much of each, how much is left

on a medical ins. policy (such as blue cross/blue shield), the policyholder may need to make copayments for prescription drugs, office visits, and procedures until the total of all copayments reaches a specified amount. suppose on the gattelaro's medical policy that the copayment for the prescription drugs is 50% of the cost; the copayment for office visits is $10; and the copayment for all medical tests, x-rays, and other procedures is 20% of the cost. after the family's copayment totals $500 in a calendar year, all medical and prescription bills are paid in full by the insurance company. the gattelaros had the following medical expenses from January 1 through April 30.

date reason cost before copayment

January 10 office visit $40
prescription $44
February 27 office visit $40
medical tests $188
April office visit $40
x-rays $348
prescription $76

a) how much had the gattelaros paid in copayments from January 1 through April 30?

b) how much had the medical insurance company paid?

c) what is the remaining copayment that must be paid by the gattelaros before the $500 copayment limit is reached?

It might help if you showed what you've tried and where you're stuck. When you reply, please also clarify how you are supposed to be applying the tools of probability or statistics to this exercise. (I can only see percentages and addition and the like, making this an arithmetic or pre-algebra question. However, it must have been assigned in your probability or statistics class, so you posted it here. But I'm afraid I'm not seeing the connection...?)

Please be complete. Thank you!

Eliz.