How to fill in the multiplication table? How many multiplication tables are there?

Filling method: horizontal graph multiplied by vertical graph.

If 2 in the vertical column is multiplied by 2 in the horizontal row, 4 is obtained and filled into the third grid in the row where the vertical column 2 is located. And so on.

One by one.

One, two, two, four

One, three, two, three, six, three, nine.

14 has 4,24 and 8,3412,446.

15, 5,2510,3515,4520,5525

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

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

18 has 8,286,3824,4832,5840,6848,7856,8864.

1999,298,3927,4936,59415,6954,79613,8972 and 998 1.

The 99-99 multiplication melody is also often called "Xiao 1999".

Ancient students learned the formula of "one for one", which ended with "10000× 10000", but it was the other way around, starting with "998 1" and ending with "one for one". Because the first two words of the formula are "99", people call it "99" for short.

Only in 13 and 14 centuries did it become our formula "one by one" ... 998 1 ".

China used the "99 formula" earlier. Sentences such as "3927", "684 18", "483 12" and "6636" can be found in books such as Xunzi, Guanzi, Huainanzi and Warring States Policy. It can be seen that as early as the Spring and Autumn Period and the Warring States Period, 99 multiplication songs became popular.

Jiujiubiao, also known as Jiujiuge and Jiuyinge, is the basic calculation rule in multiplication, division, square root and other operations in ancient China. It has been used for more than two thousand years. Pupils and some school-age children can recite it. But Europe didn't know this simple multiplication table until the beginning of 13 century.

The ancient western civilizations Greece and Babylon also invented the multiplication table, but it is more complicated than the 999 table. There are more than 1700 Greek multiplication tables invented by Babylon, and they are not complete enough. Because they worked hard to calculate multiplication and division before 13 century, people who can divide large numbers will be considered as experts in mathematics.

/kloc-At the beginning of the third century, the eastern calculation method was introduced to Europe through Arabs, and Europeans discovered its convenience, so they learned this new method. At that time, the topic of multiplying two numbers by a new method was the textbook of the university at that time.

In March of 20 15, after the multiplication table of 1999 was introduced into Britain, it was difficult to recite the formula because of different languages. The British version may be changed to "12× 12 multiplication table" after one lesson and one practice.