Get one by one.

One two equals two, and two two equals four.

One three gets three, two three gets six, and three three gets nine.

Fourteen gets four, twenty-four gets eight, 3412,446.

Fifteen gets five, twenty fifty, three five fifteen, four five twenty, five five twenty-five.

16 got 6,262,368,4624,5630,6636.

17 is 7,274,3721,4728,5735,6742,7749.

18 has 8,286,3824,48312,5840,68418,78516,8864.

Nine-tenths, 298,3927,4936,59415,6954,79613,8972,9981.

Origin:

The 99-99 multiplication melody is also often called "Little 99". Now students learn the "occupation" formula from "one by one"

From "1" to "998 1", but in ancient times, it was the other way around, from "998 1" to "22".

Four "stop. Because the first two words of the formula are "99", people call it "99" for short. About to 13 and 14.

It was only in the century that the reverse happened, as it is now.

China used the "99 formula" earlier. In Xunzi, Guanzi, Huainanzi and Warring States Policy, etc.

Sentences such as "3927", "684 18", "483 12" and "6636" can be found in the book.

It can be seen that as early as the Spring and Autumn Period and the Warring States Period, 99 multiplication songs became popular.