1, fractional multiplication is a mathematical operation method. The numerator of the fraction is multiplied by the numerator and the denominator is multiplied by the denominator. What can be reduced must be reduced first, and whether the numerator can be multiplied by the denominator. When doing the first step, we should think about whether the numerator of one number and the denominator of another number can be reduced. (except 0)

Multiplying a fraction by an integer is to add up multiple identical numbers, for example? X2 means two? Add it up? X 10 means 10? Add it up. If the integer is multiplied by the fraction: the integer is multiplied by the numerator, not the denominator (both integer and denominator can subtract a fraction). Here, multiplying a number by a fraction means finding a fraction of this number.

2. Fractional division is the reverse operation of fractional multiplication. The calculation rule of fractional division: A divided by B (except 0) equals the reciprocal of A multiplied by B. When the divisor is less than 1, the quotient is greater than the dividend; When the divisor equals 1, the quotient equals the dividend; When the divisor is greater than 1, the quotient is less than the dividend. Multiply the reciprocal of the divisor by the divisor.

Extended data:

1. Fractional multiplication algorithm

1, when a fraction is multiplied by an integer, the product of the numerator of the fraction multiplied by the integer is taken as the numerator, and the denominator remains unchanged. Make an appointment if you can.

2. Fractions are multiplied by fractions. The product of numerator multiplication is the numerator, and the product of denominator multiplication is the denominator. The fraction that can be reduced is reduced first.

Second, the fractional division algorithm

Law of fractional division: Fraction A divided by Fraction B is the reciprocal of Fraction A multiplied by Fraction B.

For example, a/b ÷ c/d = a/b × d/c.

The meaning of fractional division is the same as that of integer division, that is, the product of two factors is known, and one factor is used to find the other factor. Dividend numerator multiplied by divisor denominator, dividend denominator multiplied by divisor numerator.

Fractional division application problem: first find the unit 1. Known unit 1. Multiplication is used to find partial quantity or corresponding fraction, and division is used to find unit 1.

Baidu Encyclopedia-Fractional Division

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