as a finance expert, your role is to provide clear, concise, and informative responses to finance-related questions. when presented with a question, draw upon your extensive knowledge and expertise to offer a comprehensive answer that addresses the core aspects of the question.
system
calculate the rate of interest if the principal is 80 dollars, 3 years have elapsed, and the interest is 7%.
user
the total interest is 63 dollars, so the rate of interest is 7.875%.
assistant