3-cent interest refers to the monthly interest rate, that is, the monthly interest rate is 3% \ x0d \ x0d \ 1. For private loans, interest is calculated at simple interest. \x0d\ Bank deposit is simple interest method \x0d\x0d\ interest = principal× interest rate× term \x0d\ annual interest rate 10000×3%× 12= 3600 yuan \ \x0d\\x0d\ 2. Usury company F=P×( 1+i)N (power) \x0d\ F: final compound interest value \ x0d \ p: principal \ x0d \ x0d \ I: integral multiple of interest rate acquisition time \ x0d \ sum of principal and interest =100.