The original question is as follows:

At a gas station, there is activity, and the fuel card of 1000 is now 10% off. It costs less 0.3 yuan per liter to refuel with this card.

1. A car owner went to buy a card. How much did he spend?

2. Let the original price of petroleum be X and the current price be Y, and find the resolution function of Y about X (without writing the definition domain).

3. Xiaoming used his card to refuel, and the original price per liter was 7.3 yuan. So how much did Xiao Ming spend less per liter of oil?

First, the difficulty of the Shanghai senior high school entrance examination questions

The Ministry of Education mentioned in the Notice on the Proposition of the Senior High School Entrance Examination in 2022 that it is forbidden to expand the scope and interpretation of the proposition of the senior high school entrance examination, not to exceed the standard proposition, and not to expand or narrow the scope of the examination without authorization. In particular, it is emphasized that too much content such as high school courses and subject competition questions cannot be put into the senior high school entrance examination questions.

Therefore, it is the difficulty of the test paper, and the Shanghai middle school exam will not increase the difficulty. In order to play a role in the selection of the senior high school entrance examination, I believe the difficulty will not drop too much, and the difficulty of the previous senior high school entrance examination will be maintained.

2. Number of candidates

As a municipality directly under the central government, Shanghai has 1 10000 junior high school graduates, and the actual number of students taking the senior high school entrance examination will decrease, but it is estimated that the number of candidates this year will increase significantly compared with last year.

Third, the admission situation

Many parents are concerned about the high admission rate. In 2022, the admission rate of ordinary high schools will increase to 78%, which means that nearly 80% of Shanghai candidates can enter ordinary high schools for further study.

As for the admission of key areas and ordinary high schools, it will be carried out in the unified recruitment. I don't think there will be much change in the difficulty ranking this year. Generally speaking, the admission score in the central city is higher than that in the suburbs, and it is relatively difficult in densely populated areas such as Pudong New Area, Minhang and Jiading, and it is less difficult in suburban counties such as Chongming.

Mathematical problem solving method

1. Understand the meaning of the topic: read the topic carefully, and understand the content and problem-solving steps required by the topic.

2. Grasp the key information: determine the known conditions given in the topic and mark them accordingly to facilitate subsequent calculation and reasoning.

3. Use corresponding mathematical knowledge: according to the requirements of the topic, flexibly use mathematical concepts, theorems and formulas for calculation and derivation.

4. Pay attention to the problem-solving process: In the process of solving problems, pay attention to the reasonable arrangement of calculation steps to reduce the possibility of mistakes. At the same time, it is necessary to check and verify to ensure the correctness of the answer.