Mathematical Olympiad calculations and ingenious calculations in primary school
The following are some common types and methods of quick and clever calculations in primary school Mathematical Olympiad: ** 1. Clever calculations in addition ** 1. ** Rounding Method ** - When adding several numbers, if there were two numbers that could be added together to get a whole ten, a whole hundred, a whole thousand, etc., they could be added first. For example, 24 + 44+56, because 44 + 56 = 100 is a whole hundred, so first calculate 44+56, then add 24, that is, 24+(44 + 56)=24 + 100 = 124. - For an equation like 53+36 + 47, because 53+47 = 100 was a whole hundred,+47 could be moved with the sign to the front of +36, and then (53+47)+36 = 100+36 = 136. 2. ** Split and Rounder Method ** - In the case of 96+15, 15 was split into 15 = 4+11, because 96+4 = 100, which could be rounded up first, that is, 96+15 = 96+(4+11)=(96 + 4)+11 = 100+11 = 111. - For 52+69, since 69+31 = 100, 52 was split into the sum of 21 and 31, and then 31+69 = 100 was rounded up, which was 52+69=(21+31)+69 = 21+(31+69)=21 + 100 = 121. - When calculating 63+18+19, 63 was split into 63 = 60+2+1. Because 2+18 and 1+19 could be rounded up, 63+18+19 = 60+2+1+18+19 = 60+(2+18)+(1+19)=60+20+20 = 100. 3. ** The clever calculation of adding the same number ** - For 28+28+28, you can think of it this way, because 28+2 = 30 can be rounded up, but in the end, you have to subtract the three additional 2s, that is, 28+28+28=(28 + 2)+(28 + 2)+(28+2)-6 = 30+30+30 - 6 = 90 - 6 = 84. ** 2. Clever calculation in the substitution (position swap method)** - In an algorithm, the position of the numbers could be changed, and the order of the calculation of the numbers could be changed. For example, 632 - 156 - 232 = 632 - 232 - 156 = 400 - 156 = 244. ** 3. Clever calculations in multiplication ** 1. **"Tongbu" and "Butong" Quick Calculation Method ** - If the sum of two numbers was equal to 10, then the two numbers were complementary. In the integral multiplication operation, for example, 72×78, where the ten digits of the multiplication and the multiplication were the same, and the single digits were complementary (this kind of formula was called "same head, complementary tail" type), and 26×86, where the ten digits of the multiplication and the multiplication were complementary, and the single digits were the same (this kind of formula was called "complementary head, same tail" type), there were very simple and direct fast calculation methods. They were called the "same-complementing" fast calculation method and the "complementing the same" fast calculation method. ** 4. Other methods ** 1. ** Borrowing Method ** - Borrowing a number from a number, turning it into a whole ten or a whole hundred or a whole thousand, and finally, deducting the borrowed number. For example, 9+99 +999+9999=(10 - 1)+(100 - 1)+(1000 - 1)+(10000 - 1)=10+100 + 1000 + 10000 - 4 = 11106. 2. ** Choose a reference number ** - Among all the numbers, find that everyone is close to this number (this number is the benchmark number), first multiply the number of numbers by this benchmark number, and finally, subtract the excess. For example, 489+487+483+485+484+486+488. First find the base number 490 among these numbers, then use 490×7. Finally, subtract the excess, which is 490×7 - 1 - 3 - 7 - 5 - 6 - 4 - 2 = 3430 - 28 = 3402. Read more exciting novels for free
What are the recommendations for innovative thinking in primary school Mathematical Olympiad?
The following are some recommended books for primary school Mathematical Olympiad students: 1. " Mathematical Olympiad Star's Classic Question Bank of innovative thinking," published by China Forest Press on January 1, 2008. The author was Liu Xianguo. 2. Learning and Thinking, Thinking and Creation, also known as the Big White Book, was a set of books with more difficult questions in the learning and thinking system. 3. The 1998 Guangdong-Hong Kong Mathematical Olympiad Invitational Competition for the fourth grade examination paper can also be used as reference material. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
Numerology related calculations
Numerology was a theory that used numbers to predict and explain human fate and fortune. In Numerology, people use various numbers to represent human fate and fortune. For example, the numbers 0-9 represent different personality traits and life stages, while the number 10 represents success and wealth. Numerology calculations usually required combining and calculating numbers to obtain a prediction result. These calculations included: The calculation of the five elements of numbers: The five elements of numbers can affect the fate and fortune of humans. For example, the number wood, fire, earth, metal, and water could determine a person's character and class choice. Combination of numbers: Different combinations of numbers can produce different results. For example, the combination of the numbers 5 and 3 means that there may be some challenges and difficulties, while the combination of the numbers 9 and 2 means that there may be some success and wealth. 3. Calculating the relationship between numbers and astrological signs and dates of birth: Numerology also involves calculating the relationship between numbers and human fate by calculating the relationship between astrological signs, dates of birth, and other factors. It should be noted that Numerology is only a theory, and its predictions are not absolutely accurate. It is only for reference and entertainment.
It's best to use that kind of Mathematical Olympiad book in the fifth grade of primary school.
The choice of Mathematical Olympiad books depended on one's interests and level of mathematics. For the fifth grade students, it is recommended to choose a book suitable for the basic level and pay attention to interest and inspiration. Some examples of Mathematical Olympiad books suitable for fifth grade elementary school students include: - Elementary Mathematical Olympiad ( ) - "Primary School Mathematical Olympiad Real Reality Simulation Test Questions"( ) - Math Paradise ( ) These books cover basic mathematics knowledge and provide a variety of topics and challenges suitable for stimulating students 'interest in learning and improving their mathematical ability. Of course, he could also choose some more advanced course books to challenge his own mathematics level. It is recommended that you carefully evaluate your mathematics level and interest before buying.
Fan Sizhe's calculations
Fan Sizhe had shown his outstanding ability to calculate in the TV series Joy of Life. He was good at doing business and was very sensitive to numbers. He could easily calculate complicated numbers. Under Fan Xian's guidance, he formulated a detailed plan, opened the Danbo Bookstore, and sold " Story of the Stone " and " Banxianzhai Poetry Collection," achieving great commercial success. Therefore, Fan Sizhe was very good at calculation.
E-book on macro calculations
" Calculating the Big Balance: An Essay on Economics " was published by the Economics and Sciences Press in 2011. No e-book version was found. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
A novel recommended for writing tricks and calculations
I recommend the light novel " Everything is a Plan." It was a fantasy novel. The protagonist, Zhuge Yufeng, was intelligent and good at planning. He could strategize in all kinds of situations and play all kinds of tricks. This book was about scheming and scheming. It was very suitable for readers who liked this type of novel. In addition, there was also " I Am the Common Villain in the Fictions ". The protagonist had transmigrated to become the common villain of the three novels. In the original book, he used the advantage of the villain to push the original protagonists down from the altar. This novel was also a wonderful piece of work about counter-plots.
Reborn 50 military wives are divine calculations
Reborn 50 Military Wife Is a Divination is a novel by author Yinghu Yuhe. According to the search results, the novel described a big data administrator who was reborn in 1999 and obtained a big data system in 2019. The protagonist started a wonderful life by knowing everyone's situation twenty years later. However, other than that, the search results did not provide any more information about the novel.
The beginning of the game began with divine calculations
"'The Beginning of the Opening Begins with Divine Arithmetic' is a work. Young Master Qin is the contracted author of Feilu. He specializes in fantasy, online games, and urban topics. His representative works include 'The Beginning of the Opening Begins with Divine Arithmetic' and is ranked third on the Heaven Ascension Rankings. This work can be read online for free (no advertisements) on the relevant websites. At the same time, it can also be downloaded as a txt-based e-book. It can also be read and downloaded perfectly on the mobile phone. The novel "Battle of Yin and Yang" is equally exciting. Everyone is welcome to click and read it! "
What are the novels about fantasy calculations?
He recommended a few novels. " Divination in the Mind " was an oriental fantasy novel written by Han Xiang. It could predict good or bad luck and read all kinds of things in the world. " The Demon Lord of Ji Du in the Wilderness " was a Xianxia novel written by Chen Zhong. It told the story of a later generation otaku who crossed the Wilderness and fused with the Star Lord of Ji Du. It was a refreshing story in the Wilderness. The identity of the protagonist was very interesting. 'Super God-tier Beastmaster', a fantasy novel by Uti. Lin Heng had transmigrated to the world of the beast taming civilization. Although he wasn't a divine-tier beastmaster, his subdued beasts were super powerful, and his character settings were rich. Genius was a Xianxia novel written by Wandering Dragon. Ji Xiaotian's computing ability was extremely strong, and he was a tough and straightforward protagonist. " National Game: Hack From the Zombie Apocalypse " was a game novel written by the Empire's Black Iron Warrior. After Fang Heng transmigrated, he had a zombie clone that could hack. The early stages were generally exciting, and the later stages were wonderful. It was a godly work in the invincible novel, but the main character was evil and neutral. Overall, it was still worth watching. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>
A summary and reflection of simple calculations in life
Simple calculations were very important in life. Not only could it improve computational efficiency, but it could also achieve twice the result with half the effort when solving practical problems. The following is a summary and reflection of simple calculations in life: * * 1. Simple calculation method summary ** 1. * * The application of arithmetic laws ** - * * Commutative law and association law of addition **: Commutative law of addition, a + b = b + a, and association law of addition, a + b = a + b + c. For example, when calculating the change for shopping, if there are multiple prices added together, the calculation order can be adjusted according to these two laws. For example, if you buy a product worth 3, 5, or 2 yuan and pay the cashier 10 yuan, you can first calculate the change as 3 + 5 = 3 + 5 = 10 yuan, and the change is 0 yuan. - * * Commutativity, Association, and Assignment ** - Commutative law of multiplication <a × b = b × a><combination law of multiplication><(a × b) × c = a × (b × c)>It can be used to calculate the total price of the goods in batches. For example, if there are 20 apples in each box, each apple will cost 3 yuan. The total price of buying 5 boxes can be calculated as 20 yuan. - Multiplicational distribution law ((a + b) × c = a × c + b × c) and its variant (a × (b + c)= a × b + a × c). For example, the monthly water and electricity bill of the family is calculated. The water bill is RMB 2 per ton, the electricity bill is RMB 0.5 per kWh, and the monthly water consumption is RMB 10 per ton, and the electricity consumption is RMB 20 per kWh. The total cost is RMB 25. 2. * * Use of special number combinations ** - For example, combinations such as <2> and <5>,<25> and <4>,<125> and <8>. Calculating how many milliliters of water can a cubic container with a volume of 125 cubic centimeters hold (The density of water is 1 g/cm 3, and 1 cubic centimeter is equal to 1 milliliter). The density of water is known to be 1 g/cm 3, and the volume of 125 grams of water is 125 cubic centimeters, which can be calculated according to the formula of 1000 × 0.125 = 125 milliliter. 3. * * Method of extracting common factor **: When there are no identical numbers in the formula, but there is a numerical relationship between the numbers that is 10 or 100 times, the common factor can be extracted after transformation using the principle of product invariable. For example, when calculating the proportion of the family's annual expenditure, if the food expenditure is 3140 yuan, the entertainment expenditure is 720 yuan, the transportation expenditure is 430 yuan, and the total expenditure is 1500 yuan, calculate the sum of the proportion of the expenditure to the total expenditure. It can be converted to [3.14 × 1000 + 7.2 × 100 + 4.3 × 100 - 1500 =(3.14 × 1000 + 3.14 × 200 + 3.14 × 100 - 3.14 × 500)= 3.14 × (1000 + 200 + 100 - 500)], which can simplify the calculation process. 4. * * Borrowing and Returning Method **: If you calculate the value of [99 + 999 + 9999], it can be converted to [(99 + 1)+(999 + 1)+(9999 + 1)-3 = 100 + 1000 + 10000 - 3 = 11100 - 3 = 11097]. This method was relatively simple when calculating the addition of numbers close to the whole ten, hundred, and thousand. 5. * * Splitting Method **: For example, if you calculate <12.5 × 32 × 25>, you can split <32>> into <8 × 4>>, then <12.5 × 32 × 25>=(12.5 × 8) × (4 × 25)= 100 × 100 = 10000>. It might be used to calculate the number of combinations of some items in life, such as calculating the total volume of a cuboid combination of length, width, and height. 6. * * Using a benchmark number **: Find a more balanced number in a set of numbers to represent this series of numbers. For example, to calculate the average length of time a family member watches TV every day in a week, they are respectively 1 hour, 1.5 hours, 2 hours, 0.5 hours, 1.2 hours, 1.8 hours, and 2.2 hours. You can choose 1.5 hours as the reference number, then calculate the difference from the reference number, and then calculate the average difference. Finally, add the reference number to get the average length. 7. * * Substitution Method (Alphabet Substitution Method)**: When calculating a complex formula, letters are used to replace a part of the formula, making the calculation process simple. For example, when calculating some complicated financial income calculations, if the formula was more complicated, a part of it could be represented by letters, simplified, and then substituted into the specific numerical calculation. 8. * * Split Item Elimination Method **: This is commonly used in score calculation. First, the items in the formula are split into the sum or difference of two or more numbers. After splitting, the items can be offset. For example, in calculating the allocation of resources according to the ratio, it might be used if it involved the complex calculation of scores. 9. * * Transformation reduction method **: In the four operations, reduction is a common step. If you can't directly reduce the score, you can change the form by making up the number or splitting the number. For example, when calculating some composition ratio problems, this method might be used to simplify the calculation. * * 2. Reflection on Simple Operations ** 1. * * Teaching and Learning ** - For students, the multiplication distribution law was difficult to learn. There were many variations in its application. In the teaching process, many methods were needed to help students understand. For example, he could use a classification summary, a large number of exercises, and visual expressions to assist in teaching, but even so, students might still be confused when they applied the comprehensive application. This meant that the teaching method still needed to be constantly explored to adapt to the students 'cognitive characteristics. - When learning simple calculations, students might master each method well when they learned it separately, but there would be problems when they applied it together. This required more comprehensive practice to improve the students 'ability to distinguish and apply various simple calculation methods. 2. * * In terms of practical application ** - In daily life, many people might not fully realize the advantages of simple calculations and still use more complicated calculation methods. For example, when calculating the total price of a purchase, change, or calculating the proportion of a family's income and expenditure, if one could skillfully use simple calculations, they could save time and improve efficiency. - The ability to perform simple calculations needed to be constantly cultivated and improved. In some complex life scenarios, such as financial planning, project budget, etc., which involved a large amount of data calculation, simple calculations could reduce calculation errors and improve the accuracy of decisions. <a href="/?from=ask_words" style="color:red" target="_blank">Read more exciting novels for free</a>