1. The document discusses calculating simple and compound interest on various principal amounts with different interest rates and time periods. 2. Formulas provided include the simple interest formula I=prt and the compound interest formula B=p(1+r)n. 3. Examples are given of calculating simple interest earned over 6 years on $400 at 5% interest, and compound interest balances after 4 years on an initial $400 deposit at 5% interest compounded annually.