Profit = selling price-cost

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

Up and down amount = principal x up and down percentage

Discount = actual selling price/original selling price x 100% (discount

Interest = principal x interest rate x time

Pricing = cost+profit

Profit = cost x profit rate

Pricing = cost x( 1+ profit rate)

Profit rate = profit/cost

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

Selling price = percentage of pricing x discount.

Interest = principal x interest rate x number of periods

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

Expand:

Sales profit problem

The purchase price of a commodity is called the purchase price. The pre-sale price of goods is called the marked price or the original price. The actual selling price of a commodity is called the selling price.

Commodity profit = commodity price-commodity purchase price. Commodity price = original price (or marked price) x discount.

Commodity profit rate = commodity profit/commodity purchase price = (commodity price-commodity purchase price)/commodity purchase price.

Common profit problems are:

(a) the known purchase price, selling price and profit rate.

Example 1. The purchase price of brain products is 10000 yuan, and the selling price is 12000 yuan. What is the profit margin of this product?

Solution: let the profit rate of this commodity be x%. According to the meaning of the question:

12000/ 10000=x%

Solution: x=20

The profit margin of this product is 20%.

(2) Known purchase price and profit rate, purchase price or original price.

Example 2. The purchase price of a commodity is 250 yuan. When it is sold at a price lower than the list price 10%, the profit margin is%. What's the list price of this commodity? Solution: Let the commodity price be X yuan, which is (90%x-250)/250=% according to the meaning of the question. The solution is x=320.

The price of this commodity is 320 yuan.

(three) given the purchase price, purchase price and profit rate, ask for a discount on the purchase price or the original price.

Example 3. The purchase price of a famous brand suit is 1 1,000 yuan, and the price is 1, 500 yuan. A shopping mall wants to sell at a profit rate of not less than 5%. How much discount can the salesperson give to sell this product?

Solution: Salespeople can sell this product at a discount. According to the meaning of the question, (1500x/10-1000)/1000 = 5%, the solution is: x=7.

A: Sell the goods at a discount of 30%.

In this application problem of finding the discount number, it used to be a discount, and then the selling price was listed as "1500x", and finally x = 70% discount.