The product of a fraction and a letter, that is, a single coefficient with a letter factor, should be written as a false fraction.
When a false fraction is converted into a fraction, the numerator is divided by the denominator; When decimalizing the simplest fraction, we should pay attention to finding the greatest common factor of numerator and denominator to reduce the fraction.
Divide an object or unit of measurement into several parts on average, and such one or several parts can be expressed by fractions. In a fraction, the horizontal line in the middle is called a fractional line.
The number below the fractional line is called the denominator, indicating how many copies the unit "1" is divided into on average; The number above the fractional line is called the numerator, indicating how many copies there are.
Extended data
Matters needing attention in writing algebraic expressions:
1, the number is multiplied by the number. Generally, the multiplication sign is not omitted, but still multiplied by "×"; When a number is multiplied by a letter, the multiplication sign is generally omitted. Writing the number in front of the letter is a score, and the score should be written as a fake score. When letters are multiplied by letters, the multiplication sign is generally omitted and written in alphabetical order. The same factor is written in the form of power.
2. The division operation in algebraic expressions is generally written in the form of fractions.
3. When algebraic expressions with addition and subtraction operations need to express units, the whole expression must be enclosed and the units must be written after parentheses.
4. Generally, read before writing. Pay attention to the quantitative relationship when listing algebraic expressions, and consider whether to add parentheses.