The formula for boys and girls born in single and twin months is: seven seven forty-nine, plus the month, plus the mother's birth year, plus 19.

boys and girls have long known the formula: 7749 (49), ask the mother when she has it (plus the lunar month of the month of ovulation), subtract the mother's age (minus the age of nominal age), add 19, and divide it by 2, (don't round it off, just look at the number before the decimal point) even-numbered little princess, odd-numbered little prince. All ages and months here refer to the lunar calendar date.

Even numbers are women and odd numbers are men. Folk calculation method: two-year-old single month, one-year-old two-month pregnancy will give birth to a boy, and vice versa. Sour and spicy girl: It is said that the expectant mother loves sour food after pregnancy, which means that she wants to have a boy. If she loves spicy food, she wants to have a girl.

The probability of having a boy and a girl:

In theory, the ratio of male to female is 1:1. If there are brothers and sisters in both families, they are all men, and the next generation is women; One man and two women, the next generation is two men and one woman, very accurate. Whether it is a boy or a girl, or an individual, it should be a habit related to a certain probability.

If men drink less beer, the chances of having a boy will increase, especially men should pay special attention not to drink carbonated drinks such as Coca-Cola during the growth period, because these carbonated drinks can inactivate the Y chromosome in male sperm, thus reducing the chances of having a boy.