2. The concepts of reduction and general division are unclear: reduction is to divide the numerator and denominator of a fraction by their greatest common divisor at the same time, which makes the fraction easier. The general fraction is to change the denominator of two or more fractions into the same number, which is convenient for addition and subtraction. When using these two concepts, errors may occur, leading to wrong calculation results.
3. Wrong operation sequence: When performing fractional multiplication and division, you need to pay attention to the priority of the operation. Perform multiplication and division first, and then perform addition and subtraction. If the calculation is not done in the correct order, the result may be wrong.
4. Misunderstanding of using fractions: Fractions using fractions are in the form of the addition of an integer and a true fraction, such as 1 and1/2,2 and 3/4. When solving multiplication and division problems with fractions, the concept of fractions may be unclear, which may easily lead to calculation errors.
5. Wrong formula: When solving the problem of fractional multiplication and division, the wrong formula may be used, such as mistaking a/b×c/d for (ad)/(bc) or mistaking a/b÷c/d for (a/b)×(d/c).
6. Unit conversion error: When performing fractional multiplication and division, unit conversion may be involved, such as meters, kilograms, hours, etc. If there is an error in the conversion process, the calculation result may be wrong.
7. Ignore the precision problem: there may be precision problems when calculating decimals or fractions. For example, when comparing 3/4 with 0.75, errors may occur due to the representation of floating-point numbers. Therefore, when comparing the sizes of two numbers, we need to pay attention to the accuracy problem.