2. Single output × quantity = total output
3. Speed × time = distance
4. Work efficiency x time = total workload.
5. Appendix+Appendix = and one addend = and-another addend
Negative-negative = differential negative = negative-differential negative = negative+difference.
Factor × factor = product One factor = product ÷ another factor.
Frequency divider/frequency divider = frequency divider = frequency divider/frequency divider = quotient × frequency divider
Division with remainder: dividend = quotient × divisor+remainder
A number is divided by two consecutive numbers. You can multiply the last two numbers first, and then divide this number by their product, and the result is still the same. For example: 90÷5÷6=90÷(5×6)
6. 1 km = 1 km 1 km =1000m
1 m = 10 decimeter 1 decimeter =10 cm1cm =10 mm.
1 m2 = 100 square decimeter 1 square decimeter = 100 square centimeter
1 cm2 = 100 mm2
1 m3 = 1000 cubic decimeter
1 cm3 = 1000 cm3
1 ton = 1 000kg1kg = 1 000g = 1 kg =1kg.
1 hectare = 1 10,000 square meters. 1 mu =666.666 square meters.
1 liter = 1 cubic decimeter = 1000 ml 1 ml = 1 cubic centimeter.
7. What is the ratio? The division of two numbers is called the ratio of two numbers. For example: 2÷5 or 3:6 or 1/3, the first and second items of the ratio are multiplied or divided by the same number at the same time (except 0), and the ratio remains unchanged.
8. What is proportion? Two formulas with equal ratios are called proportions. For example, 3:6=9: 18
9. Basic properties of proportion: In proportion, the product of two external terms is equal to the product of two internal terms.
10, solution ratio: the unknown term in the ratio is called the solution ratio. Such as 3:χ=9: 18.
1 1, ratio: two related quantities, one changes and the other changes. If the corresponding ratio (i.e. quotient k) of these two quantities is certain, these two quantities are called proportional quantities, and the relationship between them is called proportional relationship. For example: y/x=k( k must be) or kx = y.
12, inverse ratio: two related quantities, one changes and the other changes. If the product of two corresponding numbers in these two quantities is certain, these two quantities are called inverse proportional quantities, and their relationship is called inverse proportional relationship. For example: x×y = k( k must be) or k/x = y.
Percentage: a number that indicates that one number is a percentage of another number, which is called percentage. Percentages are also called percentages or percentages.
13. To convert decimals into percentages, just move the decimal point to the right by two places and add hundreds of semicolons. In fact, to convert a decimal into a percentage, just multiply this decimal by 100%.
To convert percentages to decimals, simply remove the percent sign and move the decimal point two places to the left.
14. When a fraction is converted into a percentage, it is generally converted into a decimal (except for the inexhaustible, three decimal places are generally reserved), and then the decimal is converted into a percentage. In fact, to turn a fraction into a percentage, you must first turn the fraction into a decimal and then multiply it by 100%.
Divide the percentage into components, and rewrite the percentage into components first, so that the quotation that can be lowered can be made into the simplest score.
15, learn decimal component numbers and fractions to decimals.
16, greatest common divisor: several numbers can be divisible by the same number at the same time, and this number is called the greatest common divisor of these numbers. (or the common divisor of several numbers is called the common divisor of these numbers. The largest one is called the greatest common divisor. )
17, prime number: the common divisor is only 1 two numbers, which is called prime number.
18, least common multiple: the multiple shared by several numbers is called the common multiple of these numbers, and the smallest is called the least common multiple of these numbers.
19. Comprehensive score: dividing the scores of different denominators by the scores of the same denominator equals the original score, which is called comprehensive score. (Common divisor is the least common multiple)
20. Approximation: It is called approximation to change a fraction into a fraction equal to it, but with smaller numerator and denominator. (The greatest common divisor is used for divisor)
2 1, simplest fraction: The fraction whose numerator and denominator are prime numbers is called simplest fraction.
At the end of the score calculation, the score must be converted into the simplest score.
Numbers in units of 0, 2, 4, 6 and 8 can be divisible by 2, that is, they can be binary.
About integrals. A number with a bit of 0 or 5 can be divisible by 5, that is, it can be subtracted by 5. Pay attention to the use of contracts.
22. Even and odd numbers: Numbers divisible by 2 are called even numbers. Numbers that are not divisible by 2 are called odd numbers.
23. Prime number (prime number): If a number only has 1 and its two divisors, it is called a prime number (or prime number).
24. Composite number: a number. If there are other divisors besides 1 and itself, such numbers are called composite numbers. 1 is neither prime nor composite.
28. Interest = principal × interest rate × time (time is generally in years or months, which should correspond to the unit of interest rate).
29. Interest rate: The ratio of interest to principal is called interest rate. The ratio of interest to principal for one year is called annual interest rate. The ratio of interest to principal in January is called monthly interest rate.
30. Natural number: An integer used to represent the number of objects is called a natural number. 0 is also a natural number.