Three-sentence, percentages and co. - how does it go again? If you aspire to or pursue a commercial profession, there is no way around commercial calculation. But don't worry, even if you are not a math genius, calculations such as proportion, average, distribution or interest calculations will soon be no problem for you. Petra Leitert will explain all the important arithmetic operations you need in an easy to understand step-by-step manner. You will learn everything about depreciation, currency calculation, contribution margins and much more. Even more complex calculations such as repayment calculation, compound interest calculation, investment calculations and statistical calculations are not neglected. Numerous sample calculations, exercises and tips for working with Excel round off this book.