Full time tutor of ecological center goes to a university

1. No one knows how low it is. The lowest is zero, but the possibility is very small. Some time ago, the value of bitcoin has fallen below $200. After a period of correction after the Spring Festival, the price of bitcoin still hasn't reached $300. The current price is about $280<

there are multiple reasons for the continuous decline of bitcoin price since 2014. The following reasons are summarized for reference only:

in 2014, although the financing scale and financing enterprises of bitcoin start-ups are increasing, there is no killer application of bitcoin

since the end of 2013, there have been many trust crises in bitcoin. In 2013, China's central bank and other five ministries and commissions jointly issued the bitcoin risk notice. In addition to the media's interpretation and reward, ordinary people think that bitcoin has been banned by the state in China, and a large number of bitcoin players have withdrawn from the coin circle

in February 2014, Mentougou, the earliest and largest bitcoin trading platform in the world, announced that 800000 bitcoins had been stolen, and then filed for bankruptcy protection. People's confidence in bitcoin was seriously hit

the price of bitcoin continued to decline, which also led to a large number of big miners selling bitcoin, which led to a sharp drop in the price of bitcoin. In order to recover the cost, the miners and mining machine manufacturers were more unscrupulous in selling bitcoin, which eventually formed a vicious circle

since 2015, bitcoin has been stolen constantly. First of all, one of the world's largest bitcoin trading platforms, stamps revealed that $5 million worth of bitcoin was stolen, and then domestic bitcoin, bitcoin piggy bank revealed that 1000 bitcoins were stolen. The security problem of bitcoin is that potential investors stay away from bitcoin at one time

for more information about bitcoin, you can visit bitcoin home.

2. It's a total of ten times.
after being exhausted, it will appear again in an hour.
Where is the dinosaur fossil deposit?
it's like a Tyrannosaurus Rex (I didn't see it)
if it's a Tyrannosaurus Rex,
it will take 12 fragments (I don't remember whether it's 12 or 14)
to make a dinosaur fossil

3. A group of 40. If you are in group 4, you might as well buy it

if you dig by yourself, you can only dig 2 groups with full energy.

4. 1. Write the number directly.
0.45 × 2.5＝ 0.8 × 1.25＝ 0.3 × 3.6＝ 0.3 × 0.3＝ 10 × 0.07＝ 0.3 × 1.4＝ 0.05 × 7＝ 0.92 × 0.4＝ 0.2 × 0.26＝ 0.14 × 4＝ 0.02 × 0.1＝ 1.2 × 0.3＝0.2 × 0.4＝ 8.2＋1.8＝ 100－35.22＝ 2.3 × 4＝
2.5 × 0.4＝ 2.4 × 5＝ 0.22 × 4＝ 3.25 × 0＝
0.9－0.52＝ 3.99 × 1＝ 0 × 3.52＝ 12.5 × 8＝
8 ÷ 10 = 10-1.8-7.2= 0.43+3.57= 2.5 × four × 12=
0.9 × 0.8= 7.5x-3x = a+3a+7a== 1.05 × 100= 1 ÷ 0.5= 0.96 ÷ 3= 1.47 ÷ 0.7= 5.4 ÷ 6=
0.16.5 × 10= 0.56 × 100= 3.78 × 100= 4 ÷ 0.8 =
3.215 × 100= 0.8 × 10= 4.08 × 100= 1.1 × 0.2 =
0.6 × 0.8 = 3 × 0.9= 2.5 × 0.4= 3.6 × 0.4=
12.5 × 8= 50 × 0.04= 80 × 0.3 = 1.1 × 9=
0.16 × 5 ＝ 1.78＋2.2 = 9.6 ÷ 0.6 = 1.2 × 0.5-0.4 = 0.7 ÷ 0.01 = 2.5 × 0.4 = 12－3.9= 1.25 × eight ÷ 1.25 = 6.6 ÷ 0.66 = 5.37 × 0+4.63 = 3.9＋2.03＝ 4.2 ÷ 3.5＝
1.6+2.4 × 0.3 = 2.14－0.9＝ 27＋456＋73= 0.3 × 0.3=
7.2＋2.8＝ 0.9 ÷ 0.01＝ 12 ÷ 0.3= 2.87 ÷ 0.7＝
13 ÷ 4＝ 0.96 ÷ 0.3＝ 1.5 × 0.4＝ 7 ÷ 0.25＝ 2.5 × zero point seven × 0.8= 8－2.5＝ 16 ÷ 1.6＝ 5.6 × 1.01= 8 × 2.5＋0.25＝ 0.36＋0.64＝ 64.32 ÷ 16＝ 4.2 ÷ 0.1＝
72.8 ÷ 0.8＝ 8.4 ÷ 4.2＝ 13.8＋9.9＝ 2.4 × 2.5＝
0.05 × 0.8＝ 2.56－0.37＝ 1.25 × zero point eight × 0.5＝ 12 × 2.5＝ 1.23 × 3＝ 3.2 ÷ 1.6＝ 3.5＋3.5 × 3＝ 19.6 ÷ 2＝ 8.8 ÷ 2.2= 0.75 × 4＝ 1.5＋0.25 × 4＝ 0.5 × 0.8=
8.4 × 0.2= 1.6 × 0.2＝ 7.2 × 0.3= 2.8 × 0.3＝ 0.9 ÷ 0.15= 1.8 × 0.4= 5.5 ÷ 0.55= 0.08 × 100=
2.2 ÷ 0.11= 5.46＋4.54= 12.5 × 0.8= 0.35 × 0.3=
1.4 × 5= 2.8 × 4= 19.6 ÷ 4= 22.5 × 4 =
2 ÷ 1.2= 0.756 ÷ 0.36= 15.6 × 13=
0.18 × 15= 0.025 × 14= 3.06 × 36=
0.04 × 0.12＝ 3.84 × 2.6≈ 5.76 × 3 =
(keep one decimal place)
7.15 × 22 90.75 ÷ 3.3 3.68 × 0.25
16.9 ÷ 0.13 1.55 ÷ 3.9 3.7 × 0.016
13.76 × 0.8= 5.2 × 0.6 8.4 × 1.3
6.4 × 0.5 4.48 × 0.4 5.25 × 5
35.4 × 4.2 0.042 × 0.54 0.76 × 0.32
0.25 × 0.046 2.52 × 3.4 1.08 × 25
0.12 × zero point five × 0.16＝ 4.8 × 0.25＝ 0.125 × 1.4 ≈
(keep two decimal places)
2.5 ÷ 0.7 = (keep three decimal places) 10.1 ÷ 3.3 = (commercial circulation decimal)
10.75 ÷ 12.5 = (check by multiplication) 3.25 × 9.04 = (checking calculation by Division)
3. Disjunctive calculation (those that can be simplified should be simplified)
2.5 × seven point one × 4 16.12 × 99＋16.12 5.2 × 0.9＋0.9
7.28 × 99+7.28 4.3 × fifty × 0.2 64－2.64 × 0.5
26 × 15.7＋15.7 × 24 (2.275 ＋0.625) × 0.28
3.94+34.3 × 0.2 1.2 ×( nine point six ÷ 2.4) ÷ 4.8
8.9 × one point one × 4.7 2.7 × five point four × 3.9 3.6 × 9.85-5.46
8.05 × 3.4+7.6 6.58 × four point five × 0.9 2.8 × 0.5+1.58
32＋4.9－0.9 4.8－4.8 × 0.5 (1.25－0.125) × 8
4.8 × 100.1 56.5 × 99＋56.5 7.09 × 10.8－0.8 × 7.09
4.85 + 0.35 ÷ 1.4 8.7 × 17.4 - 8.7 × 7.4
12.5 × zero point four × two point five × 8 0.87 × 3.16+4.64 9.5 × 101
0.68 ÷ 5.2 -3.5 × 1.25
40.5 ÷ zero point eight one × 0.18 4.8 × fifteen ÷ 2.4 2．13. × zero × 8257
6.81+6.81 × 99 0.25 × one hundred and eighty-five × 40 4.4 × 0.8－3.4 × 0.8
(9.37+9．37+9．37+9．37) × 2．5 4．2. × 1.＋1. × 1.75
2.37 × 6.3+2.37 × 3.7 2.5 × one point two five × 0.32 3.8 × 10.1
2.5 ×( three point eight × 0.04) 7.69 × 101 3.8 × 10.1
0.25 × 39+0.25 0.125 × 72 46 × 0.33+54 × 0.33
(8 × 5.27) × 1.25 6.81+6.81 × 99 0.25 × one hundred and eighty-five × 40
6.8 × zero point seven five ÷ 0.5 3.75 ÷ 0.125–2.75 1.53+23.4 ÷ 7.2
9.5 × 99 13.5 × 0.98 12.5 × 8
2. Solving the equation:
54-x = 24 7x = 49 126 ÷ X=42
13+A=28.5 2.4X=26.4 7.5x－3x=18
5 × 1.3-2x=5.5 24x+6x=63.6 5.6x+4.4x=5.2

5. zero point three nine six ÷ 1.2= 0.756 ÷ 0.36= 15.6 × 13=

0.18 × 15= 0.025 × 1.4= 3.06 × 36=

0.04 × 0.12＝ 3.84 × 2.6≈ 5.76 × 3 =
(keep one decimal place)

7.15 × 22= 90.75 ÷ 3.3 3.68 × 0.25

16.9 ÷ 0.13=130 1.55 ÷ 3.9 3.7 × 0.16

13.76 × 1.8= 5.2 × 1.6 8.4 × 1.3

6.4 × 0.5 4.48 × 0.4 5.25 × 5

35.4 × 4.2 0.042 × 0.54 0.76 × 0.32

0.25 × 0.046 2.52 × 3.4 1.08 × 25

2.5 ÷ 0.7 = (keep three decimal places) 10.1 ÷ 3.3 = (commercial circulation decimal)

10.75 ÷ 12.5 = (check by multiplication) 3.25 × 9.04 = (checking by Division)

0.43 × 0.28= 6.45 × 0.73= 4.6 × 0.6=

8.9 × 0.05= 3.08 × 0.43= 1.5 × 26.7=

5.22 ÷ 29= 18.72 ÷ 3.6= 13.95 ÷ 3.1=

7.15 × 22 90.75 ÷ 3.3 3.68 × 0.25

1 × 34 =

2. Vertical calculation. 9.35 × 4.2 =

3. Vertical calculation. 15.07 × 9.8 =

4. Vertical calculation. 7.02 × 0.56 = (keep two decimal places)

I only have so many

6. On Sunday, September 4, soldiers are polite o weather: fine
if the middle point of "123" is an insignificant decimal point, it will become "1.23" or "12.3". If you put "456" on a small decimal point, it will become "4.56" or "45.6"... Decimal point is such a magic symbol, it can make all numbers become "small"
in unit 7, we learned the multiplication and division of decimals, which made me feel a lot
the first point: when the column is vertical, the digits should be aligned. Column multiplication vertical, there are many students often mistakenly think that is to use integer and integer alignment, decimal and decimal alignment, if you do that - a big mistake! The correct method should be like this: no matter where the decimal point is, when the column is vertical, the end of the two numbers must be aligned. Only in that way can the calculated result and the answer be correct
the second point: do not place a decimal point in the process of vertical column. This is a common fault of many students, if in the exam, the point on the decimal point, then the points dected, how much regret their own ah
the third point: be careful. A decimal multiplied by 101001000... Or a decimal divided by 101001000... Must not move the decimal point in the wrong position and direction
let's study mathematics seriously and devote ourselves to it! There are many secrets waiting for us to explore in the kingdom of decimals
1, the use of mathematics, sunny Friday
in life, there is mathematics everywhere. For example: shopping! Buy stationery! Measuring cloth and so on, all need to use mathematics. This semester, the teacher taught a new knowledge, is the decimal multiplication and division. This knowledge has helped me a lot

last night, my mother went to buy oranges together. Orange is 1.8 yuan a Jin, mother bought 4.5 Jin, should have paid 8.1 yuan. However,
I was careless and didn't know how to calculate it. It turned out to be 9 yuan. Fortunately, I took advantage of this semester's Protestant knowledge, calculated it in my mind, and immediately corrected the mistakes of

not only my aunt praised me for being smart and able to multiply and divide decimals when I was so young, but also on the way home, my mother praised me and saved her 0.9 yuan, and the knowledge I learned can be used in life. Yes! If you don't learn this math well, you will lose more than 0.9 yuan, maybe hundreds, thousands, even hundreds of millions< On Sunday morning, my grandfather and I went to the drugstore in otang and bought two boxes of tablets, weiershu. The two boxes were 44 yuan in total, and one box was 22 yuan. My grandfather paid her 50 yuan for one, and the salesperson gave my grandfather 6 yuan for another. After I found the money, I added the decimal and
to check it. Grandfather can also pay like this: 1. First give the salesman 40 yuan, then pay 5 yuan, find 1 yuan. 2. If grandfather has change, he can pay 40 yuan in advance and 4 yuan again. By accompanying my grandfather to buy medicine this time, I learned that mathematics is closely related to our life< On Sunday, my sister and I went shopping in the supermarket. I bought a bag of
, a bottle of milk and a bottle of soda for 10 yuan
bought a box of biscuits and a bottle of soda for 9 yuan. We gave the shopkeeper 20 yuan. The shopkeeper gave us 2 yuan in change. When we were going home,
said, "I want to buy another 10 tablets
." I took out the money and found that the owner gave me 1 yuan more. We went back and gave him the extra 1 yuan. The shopkeeper praised us as honest children. We were very happy when we heard that
2. Yesterday, I scored 95 in the math exam. I made a mistake in filling in the blanks and writing. The teacher reviewed the question before the exam. I didn't recite it carefully and remember it carefully. I was thinking about other things while reciting it. I didn't remember it at all. Therefore, in the exam, I couldn't think of it in any way, so I wrote "the size of the number". I didn't see the meaning of the title clearly, so I put it in“ ×” Written“ ÷”， That's wrong. When I got such a score, the first question was because my attitude was not correct, and the second question was because I didn't review it carefully. I will do these two things in the future, but I can't be careless. Teacher, I can't get satisfactory results in every exam. Since I went to
school, I have learned that the most important thing in learning mathematics is understanding. It's no use just ing other people's answers. Therefore, I will listen carefully in the future, so that I can achieve excellent results
3. Recently, our students from grade three to grade six took the math exam. In this exam, I only got 92.5 points. Carelessness made me do a lot of things. You're right. It's not that I can't do it. It's too careless. There are always some size problems. I would be better without these problems. There is a saying: "the first time you make a mistake, it may be excusable, but the second time you make a mistake, it shows that you are a" fool. " Maybe I'm the fool. My grades are like an olive. Olives are dangling around the edge of the cliff. If you are not careful,
you will "bump..." and fall. The achievement is not high if you want to. It depends on hard work. The ideal without action is Utopian. As
said, sometimes the value of a thing does not depend on people's income, but on people's pay - depending on how much you pay for it. That's right. Wisdom does not consist in erudition. We can't know everything. Intelligence does not consist in knowing as much as possible, but in knowing what is most necessary and what is unnecessary. Through this examination, I not only tested my recent knowledge, but also exposed many of my shortcomings, so that I can correct in time in the future study
4. After the test paper was sent out, I found that I didn't make careless mistakes, but I reced the seriousness. The seventh question in the blanks is the part specially marked in the book,
I don't read it carefully; There is also a question in the third part of the third question, which is also wrong because we don't look at the question carefully and think that we can't
; I should not be wrong in
because of the wrong idea in my head, so I chose the wrong question. I made mistakes not only in exams, but also in my daily life. For example, when I was writing, I often got careless and made mistakes. Later, after checking, I found that when I was doing my homework, I often did it for a while and then played for a while. It was easy to be careless,
, and make mistakes. But now I've got rid of the problem of
and I believe I'll be better after I get rid of other problems
5. A few days ago, we had a monthly exam. After I finished the math exam, I was so scared that I was afraid I would not do well in it! Yesterday, the results came out, I can't wait to know my own results. 95 points, I finally feel relieved, I finally put down a heavy stone. After the examination papers were sent out, I carefully analyzed the reasons for the mistakes as before. I sighed deeply and said, "ah, I have two questions that should not be wrong, and another one that if I believe in myself, I will definitely get 100 points. But I'm so careless, as if I had to make a few mistakes! " I think: I must remember this lesson, let this lesson always remind me, the next exam, no longer so careless, must test the best "100 points"! From this math monthly exam, I understand: no matter what you do, you should believe in yourself and be a good student with self-confidence
6. Today is Friday, and the examination papers have been handed out. When I saw the results, I couldn't believe my eyes. Only 86 points was worse than last time. I'm so ashamed and envious to see others get 100 points. I wish I could get 100 points myself. But they all blame their own carelessness. They also blame me for having a stomachache before I finished checking half of the positive papers. I really don't know what's going on. And I clearly check out a question is wrong, but did not have time to change, it closed the paper, that question 4 points, if the score of this question is added up, I can test 90 points, this test gives me a lesson: before the test, in addition to eating anything else. And check is to write fast, to be careful, do not write wrong words, otherwise the right will become wrong, and to calculate several times, write the answer faster, not careless, because after a while there will be time to check. In this month, I will work harder, because what I am facing is not the quiz, but the final exam. I will try my best to play my best in the exam and strive for better results
7. Today, the teacher asked us to use a calculator to verify the law of constant quotient in division. I give such examples as: example 1:16 ÷ 2 = 8 cases, 2:6 ÷ 2 = 3 cases 3:1200 ÷ 200=6 160 ÷ 20=8 60 ÷ 20=3 120 ÷ 20=6 1600 ÷ 200=8 600 ÷ 200=3 12 ÷ 2=6 …… …… 1.2 ÷ 0.2 = 6... There are many examples like this, so I won't write them out one by one. From the above examples, I know that in division,
and divisor expand (or rece) the same multiple at the same time, but the quotient remains unchanged< br />8 It's sunny on Saturday, February 14
today is another sunny day. When I was wandering in the street, I suddenly saw a lot of people gathered nearby. I ran in the past year. It turned out to be a prize grabbing game“ Hum, what's the fun of grabbing a prize. " I was tired of saying that when the people next to me heard it, I quickly said, "although it's not fun to catch prizes, there are big prizes, which are attractive." I asked eagerly, "what is it?"“ 50 yuan. " The man said with big eyes. On hearing this, I was excited, "such an attractive prize, what to say, I have to try." With that, I asked the owner how to grasp the law. The owner said: "this is 24 mahjong, mahjong written 12 5, 12 10, each time only 12 mahjong, if the total number of 12 mahjong target is 60, then you can get 50 yuan prize." After listening, I rolled up my sleeve and took out 5 yuan from my pocket to the shopkeeper
although I can catch it 10 times, I still didn't get the grand prize
after I got home, I thought about it and felt something was wrong. I think, if you score 60 points, you have to score 5 for all the 12 mahjong players. The best situation is to score 1 5 for the first time, 2 5 for the second time, 3 5 for the third time... It costs at least 6 yuan to score 12 5 for the 12th time. But in case the number of mahjong targets is 10 or the sum of some is the same, how many times and how much will it cost
after some consideration, I finally got to the bottom of the problem. I went to the street to find out, but it was clear on Saturday, February 28th.
today, when I was reading the newspaper, I saw such a topic: the surface area of a cone
[title] for a cone, the diameter of its bottom surface is 6 meters, and the length of any point on its top to bottom circumference is 5 meters, the surface area of the cone can be calculated
although I haven't learned how to calculate the surface area of a cone, I have learned how to calculate the surface area of a cylinder. By solving the problem of the surface area of a cylinder, I know that the surface area of a cylinder is equal to one side plus two bottom areas, while the surface area of a cone is one side plus one bottom area, and the side is a sector. Although I haven't learned it, I know how to calculate the sector by looking up the data

7. 10÷0.5=20
8.1÷3=2.7
46÷20=2.3
12÷8=1.5
你是说的这些除法运算吗

8. 50 decimal division in the first volume of the fifth grade
50 decimal division in the first volume of the fifth grade
50 decimal division in the first volume of the fifth grade