The crossword solution for the term FIXED METHOD is FORMULA. A FORMULA is a set of mathematical instructions that can be used to solve a problem or calculate a value. It is usually expressed in symbols and equations, and can be used to solve a variety of problems. Formulas are often used in science, engineering, and mathematics. They can also be used to calculate financial values, such as interest rates or stock prices. Formulas are an important part of any fixed method, as they provide a reliable way to solve problems and calculate values.