In the sixth grade mathematics course, the method of fractional multiplication and division is an important content that must be mastered. To master the simple operation method of fractional multiplication and division, we need to understand some basic concepts and laws first.

I. Basic concepts

1, numerator and denominator: a fraction consists of numerator and denominator, with numerator above and denominator below.

2. Fractional multiplication: Multiplying two fractions means multiplying their molecules separately, and the denominator remains unchanged.

3. Fractional division: Dividing one fraction by another is equivalent to multiplying this fraction by the reciprocal of another fraction.

Second, the simple operation method

1, divisor: When calculating fractional multiplication, if the numerator or denominator can be divisible by a certain number, then this number can be reduced to a fraction. For example: 2/6=(2÷2)/(6÷2)= 1/3.

2. Split: When calculating fractional multiplication, sometimes the numerator or denominator can be split into the sum of several numbers and then multiplied by another fraction. For example: (2+3)/5=(2/5)+(3/5).

3. Reduction of reciprocal: When calculating fractional division, if both numerator and denominator are reciprocal, the same number can be reduced at the same time. For example:-2/3 ÷ (-3) = 2/3×1/(-3) =-2/9.

4. Cross multiplication: When calculating the fractional division, you can cross multiply the numerator and denominator respectively to get a new fraction. For example: 4/5 ÷ 3 = (4× 3)/(5× 3) =12/15.

5. Convert to Integer: When calculating fractional multiplication, you can convert decimals into fractions, and then use the rules of fractional multiplication to calculate. For example: 0.5× 2/3 = (1/2 )× (2/3) =1/3.

Third, matters needing attention

1. When performing simple operations, follow the operation rules and don't change the operation order at will.

2. Pay attention to that the rounded number cannot be 0 when rounding, and ensure that the split number is still correct when splitting.

3. Pay attention to the change of symbols when reducing the reciprocal.

4. When cross-multiplying, we should pay attention to the effectiveness of scores and avoid invalid scores.

5. Pay attention to the position of decimal point when converting to integer, so as not to get wrong results.

In a word, in order to master the simple operation method of sixth grade fractional multiplication and division, we need to be familiar with the basic concepts and laws and use all kinds of simple operation methods flexibly. At the same time, we should pay attention to the correctness and effectiveness of the operation.