Final answer:
The average annual percentage rate (APR) for credit card borrowing is 15% per year, reflecting the compounded annual interest rate charged on outstanding balances.
Step-by-step explanation:
The student is inquiring about Rachel's annual percentage rate (APR) on her credit card. Within the context of credit card markets, where the typical interest rate ranges from 12% to 18%, the average APR cited for credit card borrowing is 15% per year.
This APR reflects the compounded annual interest rate that cardholders are charged on their outstanding credit card balances. Since Rachel's specific APR is not directly provided, we refer to the typical average which is 15% as per the information given.