Glossary (Version 8.4)

Order of operations refers to a collection of rules for simplifying expressions. It stipulates that calculations in brackets must be made first, followed by calculations involving indices (powers, exponents), then multiplication and division (working from left to right), and lastly, addition and subtraction (also in order from left to right); for example, in 5-6÷2+7, the division is performed first and the expression becomes 5-3+7=9. If the convention is ignored and the operations are performed in the order they are written, the incorrect result, 6.5 is obtained.