1 square c perimeter s area a side length perimeter = side length× 4c = 4a area = side length× side length S=a×a2 cubic v: volume a: side length surface area = side length× side length× 6s table =a×a×6 volume = side length× side length× side length V=a×a×a3 rectangular c perimeter s. Surface area (length× width+length× volume = length× width× height V=abh5 triangle s area a bottom h height area = bottom× height ÷ 2s = ah2 triangle height = area× 2 ÷ bottom triangle bottom = area× 2 ÷ height 6 parallelogram s area a bottom h height area = bottom× height. Bottom area r: bottom radius c: bottom perimeter (1) lateral area = bottom perimeter x height (2) surface area = lateral area+bottom area x 2 (3) volume = bottom area x height (4) volume = lateral area ÷ 2 x radius 10 cone v: volume h: height. Bottom area r: bottom radius volume = bottom area × height ÷3 1 × number of copies = total number of copies = 2 1 multiple × multiple = multiple ÷ 1 multiple = multiple ÷ unit price = total quantity ÷ quantity = unit price. Number of floors = number of buildings -( 1) Calculation formula of perimeter area and volume of primary school mathematics geometry 1, perimeter of rectangle = (length+width) ×2C=(a+b)×22, perimeter of square = side length× ×4C=4a3, area of rectangle = area of triangle = bottom× height \. Area of trapezoid =. Area of circle = π× radius× radius mathematical formula 10, 1 10,000 is 1000,000, 10 is 1000,000, 1 0 is10. One (1), ten, hundred, thousand, ten thousand, one hundred thousand, one million, ten million and one hundred million are all counting units. The positions they occupy are called numbers. The habit of counting in our country is four-digit classification: every four digits from the right are one level. It is divided into 10, 1 10,000 and 1 100 million levels. Each level contains 1, 10, 100,1000; Ten thousand digits include ten thousand digits, one hundred thousand digits, one million digits and ten million digits. How many "tens of thousands" does the first level represent, and how many "tens of thousands" does the tenth level represent. 4. Pronunciation of large numbers: first grade, and then read from advanced level. Levels 1 billion and 10 thousand should be read according to the pronunciation of individual grades, and then add "100 million" or "10 thousand" after them. No matter how many zeros are at the end of each level, they will not be read. Other numbers have a zero or consecutive zeros, and only a "zero" is read. 5. How to write large numbers: write high first, then write low; Whoever doesn't have the previous unit will write 0 on it. 6. Case comparison of numbers within 100 million: compare the sizes of two numbers. If the digits are the same, start from the highest point. If the number of digits is different, then the number with more digits is larger. 7. rewrite the numbers. The integer of 10,000 is rewritten as a number with "10,000" as the unit, and four zeros of each level are omitted to write the word "10,000". For integers, eight zeros of 1 10,000 and 10 are omitted when rewriting, and the word "1 100 million" is written. 8. The ancient people's counting methods are: physical counting, knotting and carving. 9. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,1… all represent natural numbers. There is no object, which is represented by 0, and 0 is also a natural number. The smallest natural number is 0. There is no maximum natural number, and the number of natural numbers is infinite. 10. The forward speed between every two adjacent counting units is 10. This counting method is called decimal counting method. 1 1. As early as the 4th century, China invented the abacus. Each bead on the abacus represents 5, and each bead on the bottom represents 1. 12.ON/C is the switch and screen clear key, and CE is the clear key. 13. The light emitted by flashlights, car lights and the sun can be approximately considered as light. . 14. A straight line has no end points and can extend to both ends indefinitely, and its length cannot be measured. Light has an endpoint, which can extend to one end indefinitely, and its length cannot be measured. A line segment has two endpoints. Can't be extended, the length can be measured. 15. The figure composed of two rays drawn from a point is called an angle. This point is called the vertex of the angle. These two rays are called the edges of the angle. 16. To measure the angle, please use a protractor. 17. The measurement unit of angle is "degree", which is represented by the symbol "degree". Divide the semicircle into 180 equal parts, and the grid of each corresponding angle is 1 degree, and write it as 1 18. The size of the angle has nothing to do with the length drawn on both sides of the angle. The angle depends on the situation of both sides. The bigger the fork, the bigger the angle. 19. An angle less than 90 is called an acute angle; An angle greater than 90 and less than180 is called an obtuse angle; An angle equal to 90 is called a right angle; The angle equal to 180 is called a flat angle; An angle equal to 360 is called a fillet. 20. Angle drawing: (1) Draw a ray so that the center of the protractor coincides with the endpoint of the ray, and the 0 scale line coincides with the ray. (2) Find the degree of the angle to be drawn on the protractor, and point a point on the scale line of the angle to be drawn. (3) Connect the point and the ray endpoint into a straight line. 2 1. Speed× time = distance/speed = time/distance = speed 22. If one factor remains the same, the product of another factor will expand (or shrink) several times.