arithmetic
Significance and counting method of four operations.
Addition meaning, subtraction meaning, multiplication meaning, division meaning, addition, subtraction, division, multiplication and check calculation.
Algorithms and simple methods, elementary arithmetic.
Additive commutative law (a+b=b+a), additive associative law (a+(b+c)=(a+b)+c), multiplicative commutative law (a*b=b*a), multiplicative associative law (a*(b*c)=(a*b)*c).
Multiplication distribution law (a*(b+c)=a*b+a*c), continuous reduction property (a-b-c=a-(b+c)) and quotient invariance property A ÷ b = (a× c) ÷ (b× c) = (a ÷.
Subtraction property: a-(b+c) = a-b-ca-(b-c) = a-b+c.
Classification of operations: addition and subtraction are called first-order operations; Multiplication and division are called two-stage operations (abbreviated).
Formulas and equations
The speed of progress between length, area and volume, and their similarities.
Quality units and progress between them.
1 ton = 1000 kg = 1000 g.
Time unit exchange rate, RMB exchange rate
1 hour =60 minutes 1 minute =60 seconds.
1 = 10.
Refer to the above content: Baidu Encyclopedia-Elementary Mathematics