Friends, in the civil service examination, the true and false questions in logical judgment are high-frequency test points, among which half-truth and half-false questions are more typical and skillful questions. Next, Zhonggong Education will lead everyone to understand this type of question and let everyone learn and master the problem-solving methods through example questions.
Let’s take a look at a classic half-true and half-false question:
examples
Kindergarten teacher Ma played the "Guess, I’m the best" game with three children Qianqian, Keke and An An. Teacher Ma said to the children: "I put the red ball, yellow ball and blue ball in my hands in the three drawers of this cabinet. Please guess what color ball is placed in each drawer? If you guess correctly, you will reward the little red flower! "Then, she asked the children to close their eyes and put the three balls in three drawers. The children guessed the following:
Qianqian said: "The red ball is in the uppermost drawer, and the yellow ball is in the middle drawer."
Coco said: "The red ball is in the middle drawer, and the blue ball is in the uppermost drawer."
An An said: "The red ball is in the bottommost drawer, and the yellow ball is in the uppermost drawer."
teacher told them that each of them only guessed half of them. May I ask: Which layer of drawers are the red ball, yellow ball and blue ball in?
A. The red ball is in the middle drawer, the yellow ball is in the uppermost drawer, the blue ball is in the bottommost drawer
B. The red ball is in the middle drawer, the yellow ball is in the bottommost drawer, the blue ball is in the uppermost drawer
C. The red ball is in the uppermost drawer, the yellow ball is in the bottommost drawer, the blue ball is in the middle drawer
D. The red ball is in the bottommost drawer, the yellow ball is in the middle of drawer, the blue ball is in the uppermost drawer
[Middle Public Analysis] Answer D.
Solution 1: Assuming that the first half of Qianqian's sentence "The red ball is in the uppermost drawer" is true, we will find that An An's two sentences closely related to Qianqian's sentence "The red ball is in the bottommost drawer, and the yellow ball is in the uppermost drawer" are false at the same time, which does not meet the conditions in the question "everyone guesses half correctly". Therefore, it is proved that it is not true that the assumption that the red ball is in the uppermost drawer" is true, that is, "The red ball is in the uppermost drawer" is false. Then I learned that Qianqian's second half sentence is true, and the yellow ball is in the middle drawer. Therefore, according to the words of the other two, the blue ball is in the uppermost drawer and the red ball is in the lowermost drawer.
In summary, we can summarize the first solution as: if one clause is associated with two clauses expressed by another, the clause must be false. In this question, in addition to Qianqian's first half of the sentence "The red ball is in the uppermost drawer" is related to An'an's whole sentence "The red ball is in the bottom layer drawer, and the yellow ball is in the uppermost drawer"; there is also Coco's "The red ball is in the middle drawer" and Qianqian's whole sentence "The red ball is in the uppermost drawer, and the yellow ball is in the middle drawer"; and An'an's "The yellow ball is in the uppermost drawer" is related to Qianqian's whole sentence "The red ball is in the uppermost drawer, and the yellow ball is in the middle drawer". Therefore, these three and a half sentences can be directly judged as false, and further quickly solve the problem.
Solution 2: There are six sentences in the question stem, each person is half right, so there are 3 true and 3 false in total. The red ball appears the most often, and they are all in the first half of the sentence, so in the first half of the sentence, 1 is true and 2 is false, and then we can find out that the second half of the sentence is 2 is true and 1 is false. In the second half of the sentence, the yellow ball appears the most, and the yellow ball can only be placed on one of the layers. Therefore, there must be fakes for "yellow ball is in the middle drawer" and "yellow ball is in the uppermost drawer". Then, the sentence "blue ball is in the uppermost drawer" is true, and then we know that the first half of the sentence of Coco is false, and the second half of An An is also fake, the yellow ball is in the middle drawer, and the red ball is in the bottom drawer.
To sum up, we can summarize the second solution as: people correspond to things, different expressions, all affirmative forms, and find unique ones. This "unique" means that a certain concept only appears once, so in this question, it can be the only color for the color, or the only drawer layer number, namely "the blue ball is on the top layer of the drawer" and "the red ball is on the bottom layer of the drawer". These two sentences can be directly judged as true under the conditions of "the correspondence between people and things, different expressions, and all affirmative forms", and further quickly solve the problem.
Zhonggong Education believes that through the above classic examples, everyone has a certain understanding of the solution methods of half-true and half-false questions. I hope everyone can find a few similar questions to practice to see if they have really mastered these two problem-solving skills, and strive to solve the problem quickly when encountering such questions in the exam room without losing points.
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-