1, addition and subtraction of fractions with the same denominator: the denominator of fractions is unchanged, and the numerator is added and subtracted. ?

2. Addition and subtraction of fractions with different denominators: first divide the fractions and convert them into fractions with the same denominator for calculation. ?

3. Fractional addition and subtraction mixed operation method: the same as integer addition and subtraction mixed operation order. ?

The operation order of fractional addition and subtraction mixed operation is the same as that of integer addition and subtraction mixed operation: in the operation without brackets, the calculation is made from left to right. In the operation with brackets, count the inside of brackets first, and then count the outside of brackets.

The commutative law and associative law of integer addition are also applicable to fractional addition.

The operation rules and methods involved in integer mixing operation are also used for addition and subtraction of fractions, so before learning this part, you can review the operation rules of integer mixing operation and some simple algorithm skills, which will be easier to learn.