Ann obtains a fully amortizing 30 year Fixed Rate Mortgage with monthly payments for $1,250,000 at 4.38%. What will be Ann's mortgage balance after 20 years of payments (ie after 240 months)? Ann obtains a fully amortizing 30 year Fixed Rate Mortgage with monthly payments for $1,250,000 at 4.38%. What percent of Ann's 20th payment goes to interest