1. Fractional multiplication of integers has the same meaning as integer multiplication, and can represent a simple operation to find the sum of several identical addends.

2. The significance of multiplying a number by a fraction lies in finding the fraction of a number. This is an extension of integer multiplication.

Second, the calculation rules of fractional multiplication

1. The fraction is multiplied by an integer, and the product of the multiplication of the fraction and the integer is a numerator, and the denominator remains unchanged.

2. Fraction and fractional multiplication, the product of molecular multiplication is the numerator, and the product of denominator multiplication is the denominator. The calculation rule is: =.

Note: in order to simplify the calculation, the points that can be reduced should be reduced first and then multiplied.

Third, the application of fractional multiplication

The application problem of "what is the score of a number" is calculated by multiplication, and the law of solving the problem is:

Example 1 a cup of pure fruit juice, Wang drinks it for the first time, then fills it with water before drinking it. Which time did he drink more juice? Why?

Obviously, Wang drank a lot of juice for the first time. Although Wang drank a glass of juice twice, they drank in different units. I drank pure juice for the first time, and then filled it with water. At this time, the remaining pure juice is 1-=. The second time I drank it. By comparison, we can see that we drank more juice for the first time.

Unit teaching material analysis

This unit is based on students' knowledge of integer multiplication and division, solving simple equations and fractional multiplication. This knowledge lays a foundation for students to learn fractional division. Learning this unit will play a good role in deepening students' understanding of calculation methods and improving their calculation ability. Textbooks include: fractional division, problem solving, ratio and the application of ratio. This knowledge is an important foundation for students to further study. Through this unit, students can learn. On the other hand, I began to learn the basic knowledge of Bi, which provided a foundation for later study of percentage and proportion. These two achievements will play an important role in further research.

Unit teaching objective

1, so that students can perceive the significance of fractional division in specific situations, master the calculation method of fractional division, and correctly calculate fractional division through oral or written calculation.

2. Let students use fractional division to solve the practical problem of finding the score of a given number.

3. Understand the meaning and basic nature of ratio, know the relationship between ratio, fraction and division, correctly find and simplify ratio, and use the relevant knowledge of ratio to solve practical problems.

4. Let students feel the value of learning mathematics in concrete and vivid situations.

Key points of unit teaching

1, the calculation of fractional division;

2. The solution of fractional division problem;

3. Understanding and application of the meaning and basic nature of ratio.

Difficulties in unit teaching

1, know the arithmetic of fractional division;

2. Application of ratio.

1, fractional division

Teaching objectives

1, understand the meaning of fractional division, guide and preliminarily master the calculation rules of fractional division by integer, and correctly calculate fractional division by integer.

2. Make students understand the arithmetic of integer divided by fraction, master a calculation method of number divided by fraction, correctly calculate a number divided by fraction, and cultivate students' reasoning and inductive ability.

Teaching focus

1. Understand that fractional division and integer division have the same meaning.

2. Learn the calculation rules of dividing scores by integers, and apply the rules to calculate correctly.

3. The arithmetic of dividing a number by a fraction.

4. Master the unified law of fractional division.

Teaching difficulties

1, learn the calculation rule of dividing fractions by integers, and correctly apply this rule to calculate.

2. Guide students to deduce the method of dividing integer by fraction.

3. Understand the algorithm of dividing a number by a fraction.