Xiao Ming s mother s store has two batches of fruit

Xiao Ming's mother's store bought two batches of fruit, and both sold to get the same amount of money. Mom said: The first batch of fruits sold at a price increase of 20%, and the second batch of fruits were sold at a price reduction of unsalable, so in the end, the two batches of fruits did not lose money. Xiao Ming's mother's statement ( ).

A, Correct B, False C, Uncertain.

Analysis: This question is close to life, taking commodity trading as the starting point, mainly testing whether students can actively and flexibly use mathematical ideas and methods to analyze and judge problems in daily life. Uncover the superficial equality of numbers and grasp the essence of the problem.

There are few known conditions in the question, and it can be seen from the question that the total price of the first batch of fruits sold is 120% of the original price; The total price of the second batch of fruits sold was 80% of the original price. The total price of the two batches of fruit sold is the same, and the total price sold can be set as an unknown number A or a known number for ease of calculation. (can be set to 96 of 12 and 8).

Solution: If the total price sold is 96 yuan.

The original price of the first batch of fruits: 96 (1+20%) = 80 (yuan) earned 80 20% = 16 (yuan).

The original price of the second batch of fruits: 96 (1-20%)=120 (yuan) lost 120 20%=24 (yuan).

16 24 Therefore the two batches of fruit together were lost.

Answer: B

The price of a garment is 600 yuan per set, and the price should be reduced. For the first time, there is a 20% discount**, each set makes a profit of 25%, and after the store sells 00 sets of such clothes, the remaining 8 sets of clothes will be discounted according to the purchase price**. When all the clothes are sold out, how much will the store make a profit?

No, it's lost.

For example, if the original price of the first batch of fruits is 5 yuan, then the price increase is 20%, which is 6 yuan to sell.

Then the second batch of fruits is also sold for 6 pieces, so it means that the original price is a piece.

The first batch rose by 1 yuan.

The second batch was downgraded.

So lost.

Let's make a profit and a loss

It's okay to find a number to substitute it

False, because the first basket refers to a profit of 20 on the basis of the purchase price, and the second basket is a 20 discount on the original price, so it should be wrong.

Xiao Ming's mother bought two batches of fruit in her store, and both sold to get the same amount of money, and her mother said that the first batch of fruit was a hot seller, selling at 220% higher than the cost price; The second batch of fruits is unsalable, and they are sold at a reduced price on the basis of cost price, in general, the two batches of fruits have not lost money, children, is it right for mom to say? Mom is not right Analysis: If the two fruits are sold out to get x yuan, the first fruit is sold at 20% of the purchase price, that is, the selling price is 1 + 220% of the purchase price, then the purchase price is x (1 + 220%) yuan, the same reason can be seen, the second fruit purchase price is x (1-1 5) yuan, calculate the purchase price of the two fruits and compare the amount of money sold later

Extended Material: Elementary School Mathematics Problem Solving Skills:

1. The thinking process of using concepts, judgments, and reasoning to reflect reality is called abstract thinking, also known as logical thinking. Abstract thinking is further divided into: formal thinking and dialectical thinking.

Objective reality has its relatively stable side, and we can adopt the way of formal thinking; Objective existence also has its ever-changing side, and we can adopt the way of dialectical thinking. Formal thinking is the basis of dialectical thinking.

2. The common method of primary school mathematics is the control method. According to the meaning of mathematical problems, the method of solving problems by relying on the understanding, memory, identification, reproduction, and transfer of mathematical knowledge is called the comparison method by comparing the meaning and essence of concepts, properties, laws, laws, formulas, nouns, and terms. The significance of this method is to train students to have a correct understanding of mathematical knowledge, a firm memory, and accurate identification.

3. The principle of extremity: analyze the problem to be studied to the extreme state, so that the causal relationship becomes more obvious, so as to achieve the purpose of quickly solving the problem. Extremes are mostly used in finding extreme values, value ranges, and analytic geometry, and many problems with cumbersome calculation steps and large amounts of calculations can be solved instantaneously by using extremes to analyze.

4. Combination of numbers and shapes: from the conditions of the question, make a figure or image that meets the meaning of the question, with the help of the intuitiveness of the figure or image, through simple reasoning or calculation, so as to get the answer. The advantage of combining numbers and shapes is that it is intuitive, and you can even use a measuring ruler to measure the results directly.

No, the number of fruits is different, so the unit "1" is different.

Poos 彡 look up, hello:

If you earn 20%, the cost is 120 (1 20%) 100, that is, you have earned 120 100 20 yuan.

Earn 20%, i.e. the selling price is 1 20% of the cost, so the cost is 120 (1 20%) 100, and earn 120 100 20

If you lose 20%, the cost is 120 (1 20%) 150, that is, you lose 150 120 30 yuan.

The loss is 20%, that is, the selling price is 1 20% of the cost, so the cost is 120 (1 20%) 150, and the loss is 150 120 30

So the total loss is 30 20 10 yuan.

Actually, the easiest way to do it is:

The total cost is: 120 (1 20%) 120 (1 20%) 250 (yuan).

Sold in total: 120 2 240 (yuan).

So the loss: 250 240 10 (yuan).

The cost price of the first box of fruit is 100

The cost price of the second box of fruit is 150

If the two bases are not the same, 20% and -20% cannot be used to indicate that there is no transfer and no compensation.

You're doing the math for that. Although it sounds the same number, both are 20%, but the base is different, so it is a loss.

The cost is 100 + 150 = 250 yuan.

It was actually sold for 120 + 120 = 240 yuan.

Loss of 250-240 = 10 yuan.

Not to the first batch 1x (1 + 20%) = , profit; If the second batch of fruits also gets yuan, it should be yuan, that is: yuan is needed to purchase, yuan. So the first batch of fruits made yuan, the second batch lost yuan, and before and after it lost yuan.

Suppose that both fruits will get x dollars after they are sold out

x÷（1+220%）

x÷320%，=5

x (yuan); x÷（1-1，=x÷4

x (guess the hunger element).

x+5x=25

x 2x Spike Return.

That is, the amount of money sold is higher than the cost, so it is not right, it should be to make money;

Answer: Mom is not right

The wrong purchase price of the first batch of fruits = 96 (1 + 20%) = 80 yuan 96-80 = 16 (earned).

The purchase price of the second batch of fruits = 96 (1-20%) = 120 yuan, 120-96 = 24 (loss).

In general, the sale of these two batches of fruit was lost.

Get $x after selling.

The cost of the first batch of fruits:

x÷（1+20%）=5

x (yuan), the cost of the second batch of fruits:

x÷（1-20%）=5

x (yuan), the cost is total:

x+5x=21

x (yuan), actually sold x+x=2x (yuan).

x 2x, Xiao Ming's mother is not right, and she loses it

So the answer is: false

Get $x after selling.

The cost of the first batch of fruits:

x÷（1+20%）=5

x (yuan), the cost of the second batch of fruits:

x÷（1-20%）=5

x (yuan), the cost is total: royal rent.

x+5x=21

x (yuan), town Lu Zhao.

Actually sold x+x=2x (yuan).

x 2x, Xiao Ming's mother is not right, and she loses it

So the answer is: wrong, wrong