Profit = cost × profit rate

Pricing = cost ×( 1+ profit rate)

Profit rate = profit/cost

Profit percentage = (selling price-cost) ÷ cost × 100%

Selling price = percentage of pricing × discount

Interest = principal × interest rate × number of periods

Sum of principal and interest = principal ×( 1+ interest rate× number of periods)

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1. Profit refers to the operating results of an enterprise in a certain accounting period. Profits include net income MINUS expenses, gains and losses directly included in current profits, etc. Net income minus expenses reflects the business performance of the enterprise in daily activities, while gains and losses directly included in the current profit and loss reflect the performance of the enterprise in non-daily activities. The gains and losses directly included in the current profit and loss refer to the gains and losses that should be included in the current profit and loss, and the final profit will lead to the change of the owner's equity, regardless of the capital invested by the owner or the profit distribution. The confirmation of profit mainly depends on the confirmation of income, expenses and profit and loss, and the determination of profit amount mainly depends on the measurement of income, expenses and profit and loss. The profits of financial enterprises include operating profits, total profits and net profits.

The characteristics of profit include:

(1) A certain profitability. It is the final financial achievement of an enterprise in a certain period of time.

(2) The profit structure is basically reasonable. Profit is measured according to the principle of proportion, which is the result of deducting income and expenses in a certain period of time.

(3) The profit of an enterprise has a strong ability to obtain cash.

(4) The factors affecting profit are complex. The calculation of profit contains a lot of subjective judgments, and the results may vary from person to person, so it is operable.

2. Interest rate refers to the ratio of interest to loan funds (i.e. principal) in a certain period. Interest rate is not only the main factor that determines the capital cost of enterprises, but also the decisive factor of financing and investment of enterprises. The study of financial environment must pay attention to the current situation and changing trend of interest rates.

Interest rate also refers to the ratio of the face value of deposits or loans (called total principal). The total interest of the lent or borrowed amount depends on the total principal, interest rate, compound interest frequency and the length of time of lending, deposit or borrowing. Interest rate is the price that the borrower needs to pay for borrowing from him, and it is also the return that the lender delays consumption and lends to the borrower. The interest rate is usually calculated as a percentage of one-year interest and principal.