Gu Jiusuan, a doctor of mathematics, woke up and became the concubine of a merchant family in the south of the Yangtze River. She was locked up in a woodshed and waited to die.
Her aunt asked her to be a concubine for a wealthy businessman who was over fifty years old, and her father planned to sell her at a good price.
Gu Jiusuan looked at the numbers full of holes in the Gu family's account book and smiled.
She used probability theory to calculate when her aunt's conspiracy would be exposed, used operations research to optimize the supply chain of Gujia Clothing Store, and used game theory to force competitors to voluntarily give up market share.
Three years later, her business name "Jiu Suantang" expanded from a corner of the south of the Yangtze River to five northern provinces.
Five years later, her book "Mathematics on Business Dao" was adopted as a teaching material by Taixue.
Seven years later, the emperor asked her in the Jinluan Palace: "Gu Jiusuan, can you clearly calculate my treasury?"
She replied: "Your Majesty, your treasury is in deficit of 37 million taels. Your minister of household affairs has embezzled 13% of it, and your governor of water transportation has embezzled 27%."
"And I can use mathematics to help you calculate every penny of Daliang Dynasty clearly."
This is the story of a mathematical genius who used calculus to gain money, probability theory to gain power, and game theory to gain men in ancient times.
