Determine the fraction of total interest owed.

after the fifth month of a 12-month loan:

the numerator is: {(n + ) + (n + ) + (n + ) + (n + ) + (n + )} = , and

the denominator is: {(n) + (n + 1) + + (n + )} = .

therefore, the fraction is numerator/denominator (to the nearest tenth) = %.