Why is the month of birth a double digit?

There are 12 months in a year, and the maximum is double digits. If you don't write the month or date as a double number, then if you were born on November 1, write 111? Those born on January 11 are also written as 111, so there is no way to distinguish them.

The correct way to write is to write 1101 when you were born on November 1, and 0111 when you were born on January 11, so it is very clear. And if it's January, it's easy to be modified, and if you add a penny, it will become November or December. Write it as 01, and others can't change it.

There are 12 months of the year, from January to December.

If the month of birth is a double digit, it means that the person may have been born in October, November or December.

1.Select the column of your BAI date.

Right-click, set the cell to be du, custom.

Input. yyyy/mm/dd

In this way, the day period is four years, two months, and two dao days.

2. Again, according to the above requirements. Just type.

yyyy/mm

I highly recommend you to use this method.

Because once the year, month and day are missing, then for Excel, it is not a standard date. For future data analysis, screening out of thin air adds a lot of trouble.

So it makes sense to use a standard date and then take advantage of the cell formatting to make a visual change (the value itself is still the standard date).

Select the preset area, right-click - Format Cells - Number - Classification - Custom, in"Type"In the box below, enter: ,"Confirm"Can.

Enter 1900 in an empty cell, copy the cell, select the data area to be processed, paste it selectively, and add it.

In the new column with the formula drag the value to +1900 with the data, and then selectively paste the selected value

The following formula is an example, the date is in column A, the value is in column B, and the sum of the values in column B for the statistical date from 2010-7-15 to 2010-7-20 (inclusive). If the light is after 7-15, then the second parentheses can be rounded. The formula can also attach a variety of conditions, for example, if the content of column C is equal to "a certain company", then it can also be added in the middle.

c1:c1000="A company")

sumproduct((a1:a1000-"2010-7-15">=0)*(a1:a1000-"2010-7-20"<=0)*b1:b1000)

This sentence is equivalent to 2020 minus the number after birth, plus the shoe size multiplied by 100. And 202o minus the year of birth is the age, which is generally a two-digit or one-digit number, and if it is a 100-year-old, this question is not valid. The first two digits of the number multiplied by 100 are naturally the shoe size, and the last two digits of 00 plus the age of one or two digits are naturally the age.

Numeric format:

value(mid(h10,11,2)) text format:

text(value(mid(h10,11,2)),0) where h10 is a cell, modify as needed.

Additive function: value() to convert a string to a numeric value.

There is no way to know for sure, there are hundreds of thousands of people born on the same day in the same year in the country.

The penultimate digit is an odd number, and the last digit is the system check digit.

The national unified 18-digit number of the ID card:

AA BB CC DDDD EE FF HH I JAA stands for province (municipality).

BB stands for city (district).

CC stands for county (district).

DDDD stands for year of birth.

The month of birth of the coarse grandson of the ee generation with the watch.

ff stands for Birth Day.

hh stands for police station**.

i represents gender (men's singles, women's doubles) Iwashi.

j stands for system check digit.

Subtract the probability that everyone was not born in the same month by 1.

Let the probability that all people are not born in the same month is x, x=1*11 12*10 12*9 12*8 12*7 12*6 12*5 12*4 12=

The probability sought is.

1-x=

There is a popular arithmetic trick on the Internet that makes people feel quite "magical": multiply your shoe size by 5, add 50, multiply the result by 20, add 1016, and subtract your birth year number, and you will find a 4-digit number, the first two are your shoe size, and the last two are your age.

Leave it alone.

This is the actual situation, and the certification unit is recognized.