This article is suitable for students of grade seven and above. If you are confused about solving practical problems related to discounts and profits, come and study with me quickly. Secretly tell you: top students will seriously reflect on the black font part and carry out related exercises training.
1 store or company profit problem
(1) Profit = sales price-purchase price
② Profit rate = profit/purchase price * 100%
Substitute Formula ① into Formula ②:
③ Profit rate = (sales price-purchase price)/purchase price * 100%= (sales price/purchase price-1)* 100%.
Convert Formula ③ into:
④ Sales price = purchase price * profit rate+purchase price =( 1+ profit rate) * purchase price
From 4:
⑤ purchase price = sales price /( 1+ profit rate)
Reflection: Do you know what this 1 is?
These five formulas are the four magic weapons to solve the profit problem. I hope the students can deduce it carefully by themselves!
Note: the purchase price is usually called the original price of the goods.
Many students are confused about the sales price, purchase price and original price, and they are stupid and confused. Let's make a detailed distinction:
Sales price: that is, the price at which goods are sold.
Purchase price: that is, the price of the goods at the time of wholesale, sometimes called the original price in the title.
Original price: sometimes the price of a commodity at the time of purchase is called the original price in the title, and sometimes the original price of a commodity at the time of sale is called the original price. I hope students can use and understand flexibly according to the known conditions.
2 promotion discount problem
Whether in supermarkets or shopping malls, we often encounter this kind of promotional activities, saying that it is 50% off today, so how to deal with this discount problem? Here is a formula to teach you how to deal with the discount problem easily:
6. Discounted quantity = selling price/list price * 10.
Example: A down jacket, the original price is 100. Now there is an activity in the shopping mall, and it is sold at the price of one in 79 yuan. How much discount is this down jacket?
According to our formula ⑥:
Discount quantity = selling price/list price *10 = 79/100 *10 = 7.9.
Down jackets are sold at 79% discount.
From Equation 6, we can draw the conclusion that:
⑦ Price = list price * (discount/10)
In other words, if the goods are known to be discounted, we can quickly calculate their selling price by:
8 price = list price * 0.a
(That is to say, the number of discounts/10 is to reduce the number of discounts by ten times, that is, to move the decimal point forward by one place).
For example, the original price of milk powder in 200 yuan is 7.5 fold, which means a discount of 2.5. When calculating its selling price, we only need to multiply the original selling price of 200 by 0.25, that is, the selling price of 50 yuan.
Combining formulas ⑦ and ⑧, we get:
Pet-name ruby original price = selling price /0.a= selling price * 10/ discount quantity.
No matter what kind of industry you are engaged in in in the future, you will encounter the problem of discount. I hope you don't miscalculate!
Value range of discount number
From Formula 6, we know that when calculating the discount, the selling price/marked price * 10 is used.
The discount, as the name implies, is that the selling price is lower than the marked price, so 0
It should be noted that what does 99% discount mean? According to the range of discount figures given above, I believe you can clearly translate the meaning of 99% discount. It's a 99% discount, not a 99% discount, but a 9.9% discount. When calculating the selling price, move the decimal point forward by one place and multiply it by 0.99.
Reflection: Have you calculated the discount problem so far?
3 the profit problem in the discount problem
First of all, let's distinguish some concepts in detail:
Discount: The discounts we usually get are just a few. The detailed discount calculation formula has been given above, just bring it into the formula for detailed calculation.
Price tag: When we go to the supermarket or shopping center, the price tag is the number marked on it.
Selling price: the price at the time of sale, which is divided into two types, one is the price marked above, and the other is the price at the time of transaction.
Original price: there are two kinds, one is the initial price of the goods, and the other is the price at the time of purchase. It's also called a price tag for easy memory. The distinction is relatively simple, and relevant occasions will be given in general topics, and distinctions related to memory can be given.
Purchase price: that is, purchase price, which has only one meaning, that is, the initial purchase price of goods, which must be used when calculating profits.
So how to calculate the profit of discounted goods? We give several formulas:
Attending profit = sales price-purchase price = original bid price * (discount number/10)- purchase price.
For example, a down jacket with a purchase price of 100 yuan will be sold at a 30% discount if it is priced in 500 yuan and the mall engages in activities. Do you want to make money or lose money?
Calculation method: Substitute into Formula 9 to calculate: profit = 500 * (3/10)-100 =150-100 = 50 > 0.
So down jackets are profitable, and each one can earn 50 yuan.
Original price = sales price * 10/ discount number = (profit+purchase price) * 10/ discount number.
Profit rate = profit/purchase price * 100%= (original bid price * (discount number/10)- purchase price)/purchase price * 100%.
Reflection: Do you know what this 100% is for?
Formula memory skills: remember simple formulas first, then substitute them into related complex formulas, and remember them in the order from ① to.
Senior high school entrance examination exercises
The purchase price of a commodity is 2000 yuan, and the bid price is 3000 yuan. When the store owner asks for a discount, the profit rate cannot be lower than 5%. How much discount can the sales manager give to sell goods?
Analysis: For the known conditions and unknown conditions given in the question, we need to find the relevant relationship, ask what to use to set the related unknowns, and finally list the equations related to the unknowns. For beginners, if the formula is not skilled, it is recommended to step by step.
Solution: Set the sales manager to sell goods at the lowest discount of X.
Judging from the known conditions: (For beginners, we answer questions in four steps)
Step 1 profit = selling price-purchase price =3000*x/ 10-2000.
The second step profit rate = profit/purchase price *100% = (3000 * x/10-2000)/2000 *100%.
In the third step, the profit rate is not less than 5%, so the profit rate = profit/purchase price = (3000 * x/10-2000)/2000 *100% > = 5%.
The fourth step is to solve x & gt=7.
The minimum discount is 30%.
Of course, if you master the twelve formulas mentioned above, you can directly solve them as follows:
Solution: suppose the sales manager can get the lowest discount of X.
(3000 * x/ 10-2000)/2000 * 100% & gt； =5%
Solution: x & gt=7
The minimum discount is 30%.
Let's stop here for this class. See you next time! If you have any questions, please leave a message below and we will give you a satisfactory answer as soon as possible!
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