Among them, addition and subtraction are called first-order operations; Multiplication and division are called secondary operations.

operation sequence

When calculating at the same level, calculate from left to right in turn;

Two-stage operation, first multiply and then divide, then add and subtract.

When there are brackets, count the inside of brackets first, and then count the outside of brackets;

When there are multiple brackets, count the brackets first, then the brackets inside and finally the brackets outside.

If there is a power, calculate the power first.

When performing mixed operations, the numbers in parentheses are calculated first, and the parentheses are from small to large. If there is a power, calculate the power first, and then from high to low.