How much money do you need to invest each month in a retirement fund with an interest rate of 7% compounded monthly in order to have a million dollars by the time you are 65. Assume you are 18.

What was the total amount that you invested?
How much interest did you make?
What's the difference between investment and interest and what equations do I use?

i = .07/12 = .0058333... (store that in calculator's memory to keep best accuracy)

n = 47*12 = 564
payment --- p

p(1.0058333...^564) - 1)/.00583333... = 1000000

solving this for p I got $227.98

Now do what you have to with this payment.