These are the finance formulas we discussed in class:

But which one do you use? See the video and "tips" below for help.

Note: I say at the beginning of the video that it's "short". It's not very short, but does contain useful information about how to choose which finance formula to use

Tips:

Understand the scenario
- One-time deposit earning interest over time: Compound Interest formula
- Multiple deposits on a schedule (e.g. each month): Savings Annuity formula
- Multiple withdrawals on a schedule: Payout Annuity / Loan formula
- Payback a loan (car loan, house mortgage, etc.): Payout Annuity / Loan formula
Pick the right version of the formula
- For compound interest there is only one version (given P, k, r, N find the future value)
- For savings annuity there are two versions:
  - You want to calculate the monthly deposit when you know the future value. Use the "d=..." version
  - You want to calculate the future value you have when you k now the monthly deposit. Use the "PN = ..." version
- For payout annuity / loans there are two versions:
  - You want to calculate the monthly withdrawal or payment amount when you know the loan amount or starting amount. Use the "d=..." version
  - You want to calculate the starting value or loan amount when you know the monthly withdrawal or payment. Use the "P0=..." version