If the fraction and denominator are the same, the denominator remains the same, and the numerator is added and subtracted. If it is a fraction with different denominators, divide it first, and then calculate it according to the addition and subtraction calculation method of fractions with the same denominator.
Note: For addition and subtraction of fractions with different denominators, the denominator of general division is the least common multiple of the original two denominators. The final result is generally required to be written in the form of simplest fraction. Fractions are added and subtracted in the same order as integers.
The addition and subtraction of fractions with different denominators are divided first, then calculated according to the law of addition and subtraction of fractions with the same denominator, the same denominator and numerator addition and subtraction, and finally divided.
Fractional addition: Fractions with denominator are added, fractions with denominator are added, denominator is unchanged, numerator is added, and finally it will be converted into the simplest fraction. Example 1: 2/9+5/9 = 2+5/9 = 7/9 Example 2:1/8+3/8 =1+3/8 = 4/8 =1/2.
Fractions with different denominators are added: when fractions with different denominators are added, they are divided into general fractions, then the fractions with the same denominator are added and calculated, and finally converted into simplest fraction. Fraction addition and subtraction: a number subtracts several fractions in succession, which is equal to the sum of this number and subtracts several fractions in succession.
Fractional subtraction: Fractional subtraction with denominator: Fractional subtraction with denominator, denominator unchanged, numerator subtraction, and finally the simplest fraction.