3×5 means the addition of five 3s.

5x3 represents the addition of three 5s.

note:

1. In the above multiplication, the factor after the multiplication sign is often taken as the multiple of the factor before the multiplication sign.

2. See the definition of multiplier and multiplicand in wiki.

Another: the new meaning of multiplication: multiplication is not a simple notation of addition.

Ⅰ? Multiplication principle: If the dependent variable f is in direct proportion to the independent variable X 1, X2, X3...Xn, and each independent variable is qualitatively different, if any independent variable f is missing, it will lose its meaning, which is called multiplication.

In probability theory, the result of an event needs to be divided into n steps, the first step 1 includes M 1 different results, the second step includes M2 different results, …, and the n step includes Mn different results. Then this event may have n = m 1× m2× m3×…× Mn different results.

Ⅱ? Addition principle: If the dependent variable F and the independent variable (z 1, z2, z3…,? Zn) is directly proportional to each other, and each independent variable has the same mass. If the dependent variable f still makes sense without any independent variables, it is addition.

In probability theory, if an event has n kinds of results, the first 1 result includes M 1 different results, the second result includes M2 different results, ... and these n kinds of results include Mn different results, then this event may have n = M 1+M2+M3+...+Mn different.

The quality mentioned above is divided according to the function of independent variables.

This principle is the quantitative expression of logical multiplication and logical addition.

Extended data

Multiplication algorithm

1, integer

(1) Multiplies the first factor by the number on each bit of the second factor from the cell;

(2) Multiply by the number on the second factor, and the last digit of the number is aligned with the second factor;

(3) adding the multiplied numbers for multiple times;

2. Decimals

(1) Find the product first according to the law of integer multiplication;

(2) Look at a factor * * *, how many decimal places there are, and count the decimal points from the right side of the product;

Step 3 score

(1) Fractions are multiplied by fractions, the product of numerator multiplication is numerator, and the product of denominator multiplication is denominator;

(2) If there is an integer, treat it as a false fraction with the denominator of 1;

(3) If you can cut the point, cut the point first.

Baidu encyclopedia-multiplication

Baidu encyclopedia-four operations