(1) Convert subtraction into addition and write it in the form of omitting the plus sign and brackets;

(2) Simplify the operation by applying additive commutative law and the associative law.

Multiply several numbers that are not equal to 0, and the sign of the product is determined by the number of negative factors. When the negative factor is odd, the product is negative; When there are even negative factors, the product is positive. And multiply their absolute values. Examples; (-10) × [-5 ]× (-0.1)× (-6) = the product is positive, while (-4)×(-7)×(-25)= the product is negative.

definition

Addition: the operation of combining two numbers into one number.

Subtraction: when two addends and one of them are known, the operation of finding the other addend.

Multiplication: the operation of finding the product of two numbers.

Division: the operation of finding another factor by knowing the product of two factors and one of them.