All elementary school math formulas are here, collect them!

Quantity relationship calculation formula 1. Unit price × quantity = total price 2. Unit output × quantity = total output 3. Speed ​​× time = distance 4. Work efficiency Number = sum – another addend 7, minuend – minuend = difference 8, minuend = minuend – difference 9, minuend = minuend + difference 10, factor × factor = product 11, one factor = Product ÷ another factor 12, dividend ÷ divisor = quotient 13, divisor = dividend ÷ quotient 14, dividend = quotient × divisor 15. Division with remainder: dividend = quotient × divisor + remainder A number can be divided by two numbers continuously. First multiply the last two numbers, and then divide the number by their product, the result remains unchanged. Example: 90÷5÷6＝90÷(5×6) 1 kilometer = 1 kilometer 1 kilometer = 1000 meters 1 meter = 10 decimeters 1 decimeter = 10 centimeters 1 centimeter = 10 millimeters 1 square meter = 100 square meters Decimeter 1 square decimeter = 100 square centimeters Geometric formula 1. Square Perimeter of a square = side length × 4 Formula: C = 4a Area of ​​the square = side length × side length Formula: S = a × a Volume of the cube = side Length × side length × side length formula: V = a × a × a2. Rectangle Perimeter of rectangle = (length + width) × 2 Formula: C = (a + b) × 2 Area of ​​rectangle = length × width formula: S=a×b Volume of cuboid = length×width×height Formula: V=a×b×h3. Triangle Area of ​​triangle=base×height÷2 Formula: S= a×h÷24. Parallelogram Area of ​​parallelogram = base =2r Radius = Diameter ÷ 2 Formula: r = d ÷ 2 Circumference of circle = pi × diameter Formula: c = πd =2πr Area of ​​circle = Radius × Radius × π Formula: S = πrr7. Cylindrical Cylindrical side area = The formula for the perimeter of the base × height: S = ch = πdh = 2πrh The surface area of ​​the cylinder = the perimeter of the base × height + the area formula of the circles at both ends: S = ch + 2s = ch + 2πr2 The total volume of the cylinder = the area of ​​the base × Height formula: V=Sh8. Cone Total volume of cone = base area × height × 1/3 Formula: V=1/3Sh9. Sum of interior angles of a triangle = 180 degrees Arithmetic concepts 1. Commutative law of addition: When two numbers are added, the positions of the addends are swapped, and the sum remains unchanged. 2. The associative law of addition: To add three numbers, add the first two numbers first, or add the last two numbers first, and then add them to the third number. The sum remains unchanged. 3. Commutative law of multiplication: When two numbers are multiplied, the positions of the factors are swapped, and the product remains unchanged. 4． The associative law of multiplication: To multiply three numbers, first multiply the first two numbers, or first multiply the last two numbers, and then multiply them by the third number. Their product remains unchanged. 5. Distributive law of multiplication: If two numbers are multiplied by the same number, you can multiply the two addends by the number, and then add the two products, the result remains unchanged. 6. Properties of division: In division, the dividend and divisor expand at the same time.Increase (or reduce) the same multiple, the quotient remains unchanged. 0 divided by any number that is not 0 is 0. 7. Equality: A formula in which the value on the left side of the equal sign is equal to the value on the right side of the equal sign is called an equation. Basic properties of equations: If both sides of the equation are multiplied (or divided) by the same number at the same time, the equation still holds. 8. Equation: An equation containing unknown numbers is called an equation. 9. A linear equation of one variable: An equation that contains an unknown number and the degree of the unknown is linear is called a linear equation of one variable. 10． Fraction: Divide the unit \”1\” evenly into several parts, and the number that represents such a part or several points is called a fraction. 11． Rules for adding and subtracting fractions: When adding and subtracting fractions with the same denominator, only add and subtract the numerators, leaving the denominator unchanged. To add and subtract fractions with different denominators, first add and subtract the common denominators. 12． Comparison of fraction sizes: Compared with fractions with the same denominator, the one with the larger numerator is larger and the one with the smaller numerator is smaller. When comparing fractions with different denominators, first make the common denominator and then compare; if the numerators are the same, the one with the larger denominator will be smaller. 13． To multiply a fraction by an integer, use the product of the numerator of the fraction multiplied by the integer as the numerator, and the denominator remains unchanged. 14． To multiply a fraction by a fraction, use the product of the numerators as the numerator and the denominator as the product of the denominators. 15. A fraction divided by an integer (other than 0) is equal to the fraction multiplied by the reciprocal of the integer. 16. Proper fraction: The fraction whose numerator is smaller than the denominator is called a proper fraction. 17. Improper fractions: A fraction whose numerator is greater than the denominator or whose numerator and denominator are equal is called an improper fraction. An improper fraction is greater than or equal to 1. 18. Mixed numbers: Writing improper fractions in the form of integers and proper fractions is called mixed numbers. 19. The basic properties of fractions: If the numerator and denominator of a fraction are multiplied or divided by the same number (except 0) at the same time, the size of the fraction remains unchanged. 20． Dividing a number by a fraction is equal to multiplying the number by the reciprocal of the fraction. twenty one. Number A divided by number B (except 0) is equal to the reciprocal of number A times number B. 22. Rules for adding and subtracting fractions: When adding and subtracting fractions with the same denominator, only add and subtract the numerators, leaving the denominator unchanged. To add and subtract fractions with different denominators, first add and subtract the common denominators. 23. Rule for multiplying fractions: Use the product of the numerator as the numerator, and use the product of the denominator as the denominator. 24. What is ratio: The division of two numbers is called the ratio of two numbers. For example: if the first and last terms of a 2÷5 or 3:6 or 1/3 ratio are multiplied or divided by the same number (except 0) at the same time, the ratio remains unchanged. 25. What is proportion: An expression indicating that two ratios are equal is called proportion. For example, 3:6=9:18