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All I want is the formulas thanks since I forgot most of them and have already come up with some word questions.

simple

Solving for the Final amount (one example)
Solving for the Principal amount (one example)
Solving for the time (one example)
Solving for the interest rate (one example)

I have the word-problems just need the formulas I know the basic formula for simple is P=rt

compound

Here is where I'm totally clueless

Solving for the Final amount (one example)
Solving for the Principal amount (one example)

The formula for compound interest is A = P(1 + r/n)^n*y or Amount = Principal (1 + rate/number of payments per year)^{numbers of payments per year * number of years invested}.

So if there was $1,000 invested for ten years, with payments made 4 times a year, at 6% you'd get Amount = 10,000 (1+.015)^10*4 for $18,140.18.

Applying simple algebra to the formula allows us to swap the amount and the principal, just divide both sides by (1 + r/n)^n*y so you get A/(1 + r/n)^n*y = P. The logical way to think of it is to consider that the growth of the money, (1 + r/n)^n*y, is the same no matter what you do. In other words, no matter how you look at it money invested at 6% per year, with 4 payments made per year will grow by a factor 1.814018 over ten years. So if you want to know how much you would have to invest to get $20,000 at the end of that time, you just divide by (1 + r/n)^n*y.

Thank you so much