A loan of $10,000 is to be repaid in 10 years according to the one of the following arrangements:

(a) monthly installments of $A in arrears with an APR of 8%,

(b) monthly payments of $B in arrears with an APR of 9.1%, with a cashback of $684 at the beginning, i.e. the loan amount is reduced by that amount,

(c) monthly payments of $C in arrears with a quoted interest rate of 7.2% on annual rest.

Calculate the sum A+B+C