Use the example given to determine the percent of total interest owed. After the fifth month of a 12 month loan, the numerator is: { 11 ) 10 ) 9 ) 8 ) 7 )} 50 , and the denominator is: {\((n) + (n + 1) + ... + (n +\) 11 )} = 78 . Therefore, the percent to the nearest tenth is 64.1 %.