In preparing for the exam, the problem of quantity relationship puzzles everyone: if you want to improve the accuracy quickly but can't calculate quickly, you can only get 25% accuracy casually. So it is necessary to learn some alternative methods in a short time.

First, the parity method.

In order to avoid the situation that students' correct rate is zero, experts will deliberately set some special options when setting options in order to get answers quickly. First, the option is set to three odd numbers and an even number, so it is more likely to choose an even number. Secondly, parity is used to predict and simplify the calculation process.

For example, there are 50 true and false questions in a test. For each correct answer, you get 3 points. Do not do or do wrong questions, 1 point. A student will get 82 points. What is the difference between the number of correct questions and the number of wrong questions?

No matter whether it is right or wrong, the score of reference analysis is odd, and the number of questions * * * has 50 channels. Finally, even odd numbers are added and subtracted, and the result is even.

Second, the divisible method.

According to the division relation provided by the stem information, choose the answer quickly.

For example, four companies, A, B, C and D, donated money to snow-stricken areas in the south. Company A donated half of the total donations of the other three companies, Company B donated 1/3 of the total donations of the other three companies, Company C donated 1/4 of the total donations of the other three companies, and Company D donated 1.69 million yuan. Four companies donated () ten thousand yuan.

1 183 D.2028

According to the analysis of references, according to the calculation that "the donation of Company A is half of the total donations of the other three companies", the total donation is a multiple of 3; According to "the contribution of Company B is 1/3 of the total contributions of the other three companies", the total contribution is a multiple of 4; According to "the contribution of Company C is 1/4 of the total contributions of the other three companies", the total contribution is a multiple of 5. So as to quickly find the answer A from the options.

And so on, first of all, we must master the methods and skills, and then brush the questions to improve the speed and accuracy of doing the questions. Come on! I hope you can stand out in the exam. Go ashore once, good luck ~