Final answer:
A national bank based in New York may typically charge credit card interest rates ranging from 12% to 18% annually, with an average rate around 15%, though some rates can be higher.
Step-by-step explanation:
The interest rate that a national bank based in New York can charge customers in all 50 states for credit cards typically varies, but credit card interest rates usually range from 12% to 18% per year. Considering the market statistics, many Americans hold credit cards and incur substantial amounts in credit card debts, with an average annual interest rate around 15%. Banks, including national banks, often offer rates that can go much higher, and it's common to receive offers with rates between 17-20%.