The Rule of 72: Estimate How Long It Takes Money to Double
Learn how the Rule of 72 estimates how long it takes money to double, see examples at different rates, and know when to use a compound interest calculator.
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Notes on the tools, the arithmetic behind them, and the privacy choices we make.
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Invoice vs Receipt: What Is the Difference and When Do You Use Each?
Learn the difference between an invoice and a receipt, when to use each, what details they should include, and how both support accurate business recordkeeping.
How Many Work Hours Are in a Year? 2,080 and Other Schedules
Learn why 2,080 hours is commonly used for a 40-hour work year, how other schedules change the total, and how to convert salary to hourly pay accurately.
Invoice Payment Terms Explained: Due on Receipt, Net 7, Net 15 and Net 30
Understand what Due on Receipt, Net 7, Net 15 and Net 30 mean on an invoice, how to calculate due dates, choose the right payment terms, and avoid payment confusion.
APR vs Interest Rate: What Changes the Cost of a Loan?
Learn the difference between APR and interest rate, how fees affect the true cost of a loan, and what to compare before choosing between loan offers.