math (0311) - Series: financial application

three formulas to remember

simple interest:

I = Prn

where:

I = interest
P = principal (original amount)
r = rate per unit
n = number of units

sort of related, learn:

A = P + I

compound interest

An = P ( 1 + r ) ^n

and the reverse..

Vn = P ( 1 - r ) ^n