How is the price of an item determined? Examples.

Price is the amount of money for which a product or service can be sold. The price of a product is determined by the law of supply and demand.
Demand should not lag behind supply, but supply should not exceed demand in order to make a profit. Example: the cost of making a knitted hat is 300 rubles, when the price is set at 600 rubles, the demand satisfied the supply, because in a nearby store similar hats are sold for 800 rubles.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.