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Anonymous users2024-02-11The answer is: September 1.
1.Xiao Ming said: "If I don't know, Xiao Qiang definitely doesn't know."
The subtext of this sentence is actually: "I should have guessed correctly, if I guessed wrong, Xiaoqiang definitely didn't know". But Xiao Ming is still not sure whether he guessed correctly or not, and Xiao Qiang needs to confirm it.
What value does m take to make Xiao Ming say that? Obviously, 6 and 12 are not advisable, if M is 6 or 12, N may be 2 or 7 - Xiaoqiang can know Mr. Zhang's birthday with a number of 2 or 7. m can only be 3 or 9, and n can only be taken in .
If m is 3, n can take three values, and the result is "If Xiao Ming doesn't know, Xiao Qiang may know (2 4, 3 8), or he may not know (3 5)." In this case, Xiao Ming's statement that "if I don't know, Xiao Qiang definitely doesn't know" is not in line with the facts, and Xiao Ming is not enough to say so confidently.
If m is 9, then Ming knows that n can only be 1 or 5. At this time, Xiao Ming's guess is n=1, and whether n is 1 or not, Xiao Ming is not sure, if n is not 1 but 5, then Xiao Ming said "If I don't know, Xiao Qiang definitely doesn't know". At this point, in fact, Xiao Ming already knows, and there are only two situations, just waiting for Xiao Qiang to confirm whether n is 5.
2.Xiaoqiang said: "I didn't know it at first, but now I know."
Xiaoqiang said, "I didn't know about it originally", verifying that n is indeed not 2 or 7; At the same time, Xiaoqiang also knew that "M is not 6 or 12, M only has 3 and 9 to be preferable". If n is 5, then Xiaoqiang should say "I didn't know it originally, but I still don't know it now". According to the inference of the first section, n = 1, so Xiaoqiang can say "I didn't know it at first, but now I know".
3.Xiao Ming said: "Then I know too".
Xiao Ming is waiting for Xiao Qiang's words, no matter what Xiao Qiang does, Xiao Ming will know the correct answer. If Xiao Qiang says "I still don't know", then Xiao Ming can still know that "only n=5 will make Xiao Qiang at a loss", so the answer is September 5; If Xiaoqiang says "I know", then it must be September 1.
In fact, from beginning to end, Xiao Ming understood, he only needed Xiao Qiang to say Juhua to verify his guess, for Xiao Ming, it was a multiple-choice question of either A or B. Therefore, according to the story development clue of the topic itself, Xiao Ming's third sentence can be omitted, but many people use this condition when deriving - that is a bit like doing a math problem.
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Anonymous users2024-02-10Let's reason sentence by sentence.
1.Xiao Ming said: "If I don't know, Xiao Qiang definitely doesn't know."
It means that there must be no separate date in the correct month, or Xiao Qiang may know it, Xiao Ming will not say that he definitely does not know. Then June and December (because there are June 7 and December 2) can be ruled out. Only March and September remain.
2.Xiaoqiang said: "I didn't know it at first, but now I know."
I didn't know, but it means that it is not the 7th or the 2nd, then the day is 1, 4, 5, 8, and now I know, it means that after excluding June and September, there is only one month left corresponding to the correct day, so it cannot be the 5th, but 1, 4, 8 of them.
3.Xiao Ming said: Oh, then I know too.
Xiao Ming also knew, which means that the month is not a duplicate, only September 1st.
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Anonymous users2024-02-09The analysis of the return order can be done simply, and the answer is shown in the block diagram.
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Anonymous users2024-02-08Solution: 7x 3=
The two sides of the equation are multiplied by 3.
7x = the front shed on both sides of the equation is divided by 7 to get the wisdom and the rule. x=
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Anonymous users2024-02-072x 7 dec x 6 dec. 7x 5 dec. 7x 3-x -3x 3x
2x 7 dec. 2x 5 x 5 x 6 x 4 dec. 5x 5 dec. 5x 3-x 4-x 2x 3 dec. 2x-5x 3
There is an x once term, which cannot be expressed by x ten 1.
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Anonymous users2024-02-06The investigation is the monotonicity and symmetry of the slow and stupid numbers, such as disturbing the dry and the picture is defeated, and the hope.
It's all the same formula:
First + Last)*Number of Items 2 >>>More
Mathematics: Listen carefully in class, not only stop at the answer to this question, but also pay attention to the analysis methods and ideas, and pay attention to the summary. Every week, I regularly turn over the wrong questions and constantly consolidate these unfamiliar ideas. >>>More
Characteristics of information matching propositions: 1Absolutely out of order. Since the purpose of the question is to match the details of the information with the passages in the text, it is not possible to write the questions in the order of the passages. >>>More
Meaning: yì yì
1.It refers to the ideas and principles contained in things. >>>More
The most important thing is that if the picture has nothing to do with the picture, it will not put a picture into it, and the question often involves the information given in the picture, so as to involve the knowledge you have learned, in fact, to put it bluntly, as long as you have a solid foundation, look at the picture in the picture problem is just to withdraw your knowledge points, do the picture problem, you also have to pay attention to the following materials and text prompts, often a lot of important information can be found in it (other articles are also like this, material questions can often find the answer in the material, fasten the material analysis points are obtained).