Profit rate = profit/cost × 100%= (selling price/cost-1) × 100%.

Up and down amount = principal × up and down percentage

Discount = actual selling price ÷ original selling price× 1 00% (discount <1)

Interest = principal × interest rate× time

After-tax interest = principal × interest rate × time ×( 1-20%)

Operating profit is the main source of enterprise profits. Refers to the profits generated by enterprises in their daily activities such as selling goods and providing services. Its content is the balance of main business profits and other business profits after deducting period expenses.

Among them, the main business profit is equal to the main business income MINUS the main business cost and turnover tax that the main business should bear, which is usually also called gross profit. Other business profit is the difference between other business income and other business expenses.

Operating profit = main business profit+other business profit-operating expenses-management expenses-financial expenses.