5×4=20

Pronunciation: 4×5=20

Reading: Four times five equals twenty.

Note: In the current textbooks, only "multiplication" is said, not "multiplication". Pay attention to the difference between division and division.

Extended data:

Meaning of multiplication:

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.

First, the principle of multiplication: If the dependent variable F is directly proportional 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 there is a direct ratio between the dependent variable F and the independent variables (z 1, z2, z3…, zn), and the quality of each variable is the same, it is still meaningful to lack any independent variable F, that 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.

References:

Baidu encyclopedia-multiplication