I'm trying to learn java. So I'm practicing what I've learned so far by making a calculator to do formulas I learned in my finance class. But it's not working right now. Code (Text): case ("loan length"): Scanner inp_ll = new Scanner(System.in); System.out.print("What is the monthly payment? "); monthlypmt = inp_ll.nextDouble(); System.out.print("What is the rate? "); percent = inp_ll.nextDouble(); rate = percent/100; System.out.print("What is the loan amount? "); principal = inp_ll.nextDouble(); answer = (Math.log(monthlypmt/principal)-Math.log((monthlypmt/principal)-(rate/12)))/12*Math.log(1+rate/12); System.out.print(("The loan length is: ")+ (answer)); break; Here's one input I tested And then another input using bigger numbers yields Did I just do the formula wrong? I looked it over a bunch and it looks right to me. I even erased it and tried typing it in again. Here's the original formula where ln is natural log, m is monthly payment, p is principal and r is rate.