Please show me how I would be able to get this answer on the calculator. I could get the answer using excel but do not understand how to go about getting the right answer on calc.

Question 7 1 / 1 point On a 30-year, fixed rate monthly mortgage with a 3.5% APR compounded monthly, how long does it take before the majority (i.e. > 50%) of your payment starts going toward principal rather than interest? Try solving and using calculator functions vs solving in Excel. Hint: Assume a loan amount. 7 year, 8 month 10 year, 3 month 17 year, 1 month 15 year