A math problem, use your brain

The younger brother's 2 yuan is included in the 27 yuan borne by 3 people.

The three of them spent a total of 27 yuan.

The 25 yuan in the store plus the 2 yuan for the younger brother is exactly 27 yuan. That's right.

The 27 yuan paid by the three should be added to the 3 yuan recovered to make the original 30 yuan. 2 should not be added. The younger brother's 2 yuan is included in the 27 yuan borne by 3 people, and 27 cannot be added to 2.

And what is the addition of the 27 paid by the three of them and the 2 yuan received by the younger brother? Is it shared by four people, or is it lost by four people.

Suppose the three of them paid 27 yuan, and the younger brother paid 2 yuan, the sum is the total amount of money paid by the four people. But this gain and loss cannot be added up.

The algorithm is wrong, and the difference of 1 yuan is naturally wrong.

The younger brother swallowed 2 yuan, and the boss collected 25 yuan, 9 yuan per person, 3 27

The algorithm you are talking about is sincerely deceptive.

The three of them paid a total of 30 and recovered 3, so the three of them spent 27, and the 27 was swallowed by the younger brother and 25 by the boss.

The younger brother and the boss took a total of 27 yuan, and each of the three took one yuan.

Of the 27 yuan spent by the three people, 25 yuan is in the boss's place, and two yuan is in the younger brother's place, so the 27 yuan spent by the three people cannot be added to the 2 yuan taken by the younger brother.

The $27 they spent can't be added to the $2 they stolen!

The three of them paid a total of 25 yuan for the room, plus the two yuan that the waiter swallowed alone, plus the 3 yuan that was returned to them, which was exactly 30 yuan.

x 2+y 2-4x-4y+5=0 means a circle with the center of (2,2) and a radius of root number 3, and when the straight object calling line x+y=9 is tangent to it, there is a maximum distance and a minimum distance.

So the difference between the maximum distance and the minimum distance is.

The diameter of the circle, which is 2 times the root number 3

Thank you for the Wangzhou Ant Bureau.

For a total of 14 days, Xiaojie stayed for 10 consecutive days, so Xiaojie stayed at least the fifth day, and the number of days Xiao Liu lived did not coincide with the number of days Xiaoben lived.

Then 2 in the case.

1.Xiao Liu lived for 6 days before Xiao Ben lived for 8 days.

2.8 days before Xiao Ben stayed, and 6 days after Xiao Liu stayed.

Small card 5 days and small 1 8 days with the small book 8 days to live.

If it is a fill-in-the-blank question, there are many answers, 11, 12, 13, 14, 1, 2, 3, 4 can be multiple-choice questions, and the multiple-choice question can only be A.

First of all, the number of days that Guo Xiaoliu lived and the number of days that Xiaoben lived did not coincide, they added up to exactly 14 days, and only one person lived one day at a time, only one of them could be one of them, because one person lived for 10 consecutive days, Xiaojie's absence could only be the first 4 days and the last 4 days, and only A met the conditions in all options, and there was a possibility.

It's not just the third day, maybe just one person, but all of them.

And from the options, the answer is A

It's a total of 14 days, Xiao Liu has 6 consecutive days, and Xiaoben has 8 consecutive days, which adds up to exactly 14, and they don't coincide, that is, there is at least one person every day for 14 days.

Then the question becomes Xiaojie, Xiaoka, Xiaoyi, and the three may not be there on any of the days, because Xiaojie has lived for 10 consecutive days, so he may only be the first four days and the last four days when he is away, and Xiaoka Xiaoyi may not be there in these eight days, so the correct answer is the first four days and the last four days, so choose A

It's actually quite simple to use the method of elimination.

6+8=14 Imagine a scale with 14 ticks.

Use a 10-length ruler to move it up to 4 in front and 11 in the back, so that the BCDE is excluded.

If only E were the 11th day, that would be right!

This graphic looks like this:

Draw a cube and truncate 8 vertices with a plane. When truncated, the vertices become triangular bevels.

One vertex connects 3 edges 3*24=72 Because each edge has two vertices, 72 divided by 2 gives 36

24*3/2=36

There are 24 vertices, each with 3 edges, and each edge is a line of two vertices, so it can only be counted halfway.

So there are 36 in total.

This original problem is a mathematical problem: The Law of Dividing Horses Before he died, a rich man called his three sons to his side and said, "There are 17 horses in the family that can be used as inheritance, the eldest son gets 1 2, the second son gets 1 3, and the third son gets 1 horse, and 1 2 is 8 and a half. The three sons were puzzled, so they asked Zhibo from the village to help solve the problem.

Zhibo thought about it again and again, and finally found the answer: he brought a horse from his own house to make 18 horses, the eldest son got 1 2 is 9 horses, the second son got 1 3 is 6 horses, and the third son got 1 9 is 2 horses. 9+6+2 is equal to 17 horses, and there is one horse left, which Zhibo brought from his own house, so he naturally brought it back.

The profound mathematical principles reflected in this lantern riddle can only be explained by mathematicians, but the life principles it contains are deeply enlightening.

Examples abound in everyday life. Take out the "one horse" yourself, solve the problem first, and then bring back this "horse" or even more "horses". A father was defrauded of 50,000 yuan in fake Peruvian currency and became ill.

The filial sons and daughters immediately gave 2,000 yuan to their fathers and tried to help the public security officers track down the criminals. My father was comforted, his illness was soon cured, and although the family was ruined, the whole family became more harmonious.

The father left 17 sheep to his son, and left a will to the eldest son 1 2, the second son 1 3, and the younger son 1 9, and asked how to divide the sheep?

In ancient times, in the beautiful Xinjiang, there was a wise embodiment of riding a donkey upside down - the clever and witty Avanti, who traveled all over Xinjiang, shared the worries of the poor, and skillfully fought against the stupid authorities. Once, he met three brothers arguing over a share of the inheritance. It turned out that the father of the three brothers left his last words before his death, and the inheritance he left after his death was 17 sheep, the eldest of which was 1 9, the eldest of which was 1 3, and the third of the youngest, 1 2.

And he has repeatedly told that the whole sheep must be divided, and it cannot be slaughtered. The three brothers were divided back and forth, and they could not divide each other well, and the neighbors could not do anything about their problems, so they did not give in to each other and quarreled non-stop.

The story goes that once upon a time, there was an old landlord who called his three sons when he was about to die, and said to them: "I'm going to die, and there is actually nothing straight at home, only 17 sheep, the eldest has a wife and children, so give him 1 2, and the second is about to get married, so give him 1 3, the 3rd is still a child, and only give you 1 9." The old landlord hung up after finishing speaking, leaving this question for them, the boss thought, 17 is only divided by 2, so how to divide it?

Even if there are 16, 16 divided by 2 equals 8, and 16 divided by 3 equals .........He thought about it and found that it was wrong, how to divide 17? It is impossible for us to slaughter a sheep and eat it, they are puzzled.

To get to point A, the distance traveled is a multiple of 100, and if it is x minutes when we meet, then there are 80x=100m (m: the number of laps taken by A when they meet) and 50x=100n (n: the number of laps taken by B when they meet) and reduced to x=(5 4)m

x=2n, so by 5m=8n, so m is minimum 8, n minimum is 5, i.e. x minimum is 10 minutes.

1. Walking along the 100-meter runway, A walks 80 meters per minute, A needs 100 80 = minutes 2, Walking along the 100-meter runway, B walks 50 meters per minute, B needs 100 50 = 2 minutes 3, how many minutes does it take for the two to meet again at point A? This time is a common multiple of minutes and 2 minutes, and at least how many minutes will be used to meet again at point a, then this time is the least common multiple of minutes and 2 minutes.

4. The least common multiple of minutes and 2 minutes is 10 minutes (minutes = 75 seconds, 2 minutes = 120 seconds, and the least common multiple of 75 and 120 is 5*3*5*8=600 seconds = 10 minutes).

5. It will take at least 10 minutes for the two to meet again at point A.

6. Column: 100 80 = minutes.

100 50 = 2 minutes, 2 = 10 (minutes) or minutes = 75 seconds, 2 minutes = 120 seconds 75, 120 = 600 seconds = 10 minutes.

My brother is 16 years old, my sister is 11 years old, me.

We know, two du's personal.

The age difference will not change, according to the elder brother said to the younger sister, I am as old as you replied when you were only six years old, the younger sister said to the elder brother, you were twenty-one years old when I was as old as you, the elder brother returned to the younger sister's age and the younger sister to the elder brother's age, all of them went through a different age difference, so, 6 years old to 21 years old is actually 3 their age difference, then, their age difference is (21-6) 3=15 3=5 , 21-5=16 ,6+5=11 so My brother is 16 years old and my sister is 11 years old.

The elder brother and sister are x and y years old.

y-(x-y)=6

x+(x-y)=21

Solution: x=16 y=11

A: My brother and sister are years old.

Solution: Brother She.

Brother Bai is y years old this year, and my sister is dux years old this year.

So when the elder brother is x years old, the younger sister is 6 years old, when the elder brother is 21 years old, and the younger sister is y years old.

Default condition: The age difference between brother and sister is constant.

Columnable equations: x-6=21-y, y-x=x-6, y-x=21-y, choose any two of these equations to solve: y=16, x=11, that is, the elder brother is 16 years old, and the younger sister is 11 years old.

My brother is 16 years old, bai

My sister is 11 years old. The key to solving the problem: the year du

The age difference remains unchanged. Solution and answer process: If the elder brother is A and the younger sister is B, the age difference is A-B.

According to "Brother Quan said to his sister, I think you were only six years old when you were that old" can get b-(a-b)=6, and according to "My sister said to my brother, I was twenty-one years old when I was your age" can get a+(a-b)=21. The bimodal column yields a = 16 and b = 11

11 and 16 years old. Use the age difference to equal the two binary equations.

Their imaginary scenes form a series of equal differences, and the tolerance is the age difference of (21-6) 3=5, so the age of the younger sister is 6+5=11 years old, and the older brother is 11+5=16 years old.

30 yes.

25 yes. Find 5 pieces, right?

I hid 2 pieces, right?

1 piece for one person, right?

That is, you don't add 2 pieces to it.

You directly add 25 pieces plus 3 pieces.

28 pieces, right?

Isn't there only 2 yuan left, in fact, the person staying in the hotel didn't spend 9 yuan for one person.

Instead, the three of them spent a total of 28 yuan.

Think of it this way. You get the idea!

This is a divergent thinking exam question, as if it is in a cross talk segment! Also called the concept of confusion!

Brother and sister are respectively bridge Jian Jing is x and y years old.

y-(x-y)=6

x+(x-y)=21

Solution: x=16

y=11A: The elder brother and sister Min Shen are respectively years old.