Interest ```Simple Interest r is annual rate as a decimal P is principle n is number of years A is present value A = P(1+nr) Compound Interest Interest compounded annually A = P(1+r)ᴺ r is annual rate as a decimal P is principle N is number of years A is present value Interest compounded biannually A = P(1+(r/2))^(2n) r is annual rate as a decimal P is principle n is number of years A is present value Interest compounded quarterly A = P(1+(r/4))^(4n) r is annual rate as a decimal P is principle n is number of years A is present value Interest compounded monthly A = P(1+(r/12))^(12n) r is annual rate as a decimal P is principle n is number of years A is present value Interest compounded daily A = P(1+(r/365))^(365n) r is annual rate as a decimal P is principle n is number of years A is present value Interest compounded continuously A = Pe^rt e = 2.718282 r is annual rate as a decimal P is principle A is present value t is loan period in years Mortgage payment A = Pr / (1 – (1 + r)⁻ⁿ) A is the periodic amortization payment P is the principal amount borrowed r is the percentage rate per period; for a monthly payment, take the Annual Percentage Rate (APR)/12 n is the number of payments; for monthly payments over 30 years, 12 months x 30 years = 360 payments. ``` Home Area, Volume Atomic Mass Black Body Radiation Boolean Algebra Calculus Capacitor Center of Mass Carnot Cycle Charge Chemistry   Elements   Reactions Circuits Complex numbers Constants Curves, lines deciBell Density Electronics Elements Flow in fluids Fourier's Law Gases Gravitation Greek Alphabet Horizon Distance Interest Magnetics Math   Trig Math, complex Maxwell's Eq's Motion Newton's Laws Octal/Hex Codes Orbital Mechanics Particles Parts, Analog IC   Digital IC   Discrete Pendulum Planets Pressure Prime Numbers Questions Radiation Refraction Relativistic Motion Resistance, Resistivity Rotation Series SI (metric) prefixes Skin Effect Specific Heat Springs Stellar magnitude Thermal Thermal Conductivity Thermal Expansion Thermodynamics Trigonometry Units, Conversions Vectors Volume, Area Water Wave Motion Wire, Cu   Al   metric Young's Modulus