2. Multiplying a number with a fraction is to find a fraction of this number, and finding a fraction of a number is calculated by multiplication.
3. Fractions are multiplied by fractions, the product of numerator multiplication is numerator, and the product of denominator multiplication is denominator.
4. Two numbers whose product is 1 are reciprocal.
5. The reciprocal of 1 is1,and 0 has no reciprocal.
6. The product of a number multiplied by a true fraction (a number less than 1) is less than the original number; The product of a number multiplied by a false fraction greater than 1 (a number greater than 1) is greater than the original number.
7. The reciprocal of true score is false score, which is greater than1; The reciprocal of a false score is the true score or 1, less than or equal to 1.
I don't know, ...