Chapter 3.1, Problem 88E

A payday loan is a short-term loan that is repaid on the next payday, often by giving the lender electronic access to a personal checking account. Some states have statutes that regulate the fees that may be charged for payday loans. In Problems $87\text{-}90$, express the annual interest rate as a percentage, rounded to the nearest integer.

In Illinois, charges on a payday loan may not exceed $\text{\$15}\text{.50}$ per $\text{\$100}$ borrowed. Find the annual interest rate if $\text{\$400}$ is borrowed for $13$ days at the maximum allowable charge.