Question 1160269
the repair bill is 900.
there is an 18 dollar processing fee for every 100 dollars that she borrows.
the processing fee on 900 is 9 * 18 = 162 dollars.
at the end of the month, she was able to pay 175 dollars.
that left 725 dollars that she had to borrow at 47% apr compounded daily.


47% apr compounded daily, assuming 365 days in a year, would have an effective interest rate of (1 + .47/365) ^ 365 = 1.599510519 - 1 = .599510519 * 100 = 59.9510519% per year.


the interest rate per day is .47/365 = .0012876712 * 100 = .12876712%.


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your solution is an effective interest rate of 59.9510519% per year, based on a nominal rate of 47% per year compounded daily, assuming 365 days in a year.


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if you assume it took her one whole year before she could pay back the $725 dollars, then she would have to pay a total of 1.599510519 * 725 = 1159.645126 dollars.
750 of that would be the principal and the rest would be interest on the principal.


here's two pictures, the first of the first few day calculations, and the second of the last few day calculations.


<img src = "http://theo.x10hosting.com/2020/060101.jpg" alt="$$$" >


<img src = "http://theo.x10hosting.com/2020/060102.jpg" alt="$$$" >