Compound interest on Borrowed Money

P is the principal (the initial amount you borrow or deposit)
r is the annual rate of interest (percentage)
n is the number of years the amount is deposited or borrowed for.
A is the amount of money accumulated after n years, including interest.
When the interest is compounded once a year:
A = P(1 + r)n
( n represents raised to the power of n )
Monthly = P (1 + r/12)12 = (monthly compounding - raised to the 12th power)