Four basic operations:
Addition: a+b = c
Subtraction: a-b = c
Multiplication: a × b = c
Division: a ÷ b = c
Numbers and counts:
Number sequence: 1, 2, 3, ...
Natural numbers and integers: 0, 1, 2,-1, 2, ...
Representation of decimals, percentages and fractions
Geometry:
Rectangular: perimeter = 2 (length+width) and area = length × width.
Square: perimeter = 4 × side length, area = side length 2.
Circle: perimeter = 2πr, area = πr^2.
Triangle: perimeter = side 1+ side 2+ side 3, area = bottom × height /2.
Time and date:
Clock and time representation
Calendar and date representation
Fractions and decimals:
Addition, subtraction, multiplication and division of fractions
Fractional addition, subtraction, multiplication and division
Percentages are converted into fractions or decimals
Average and median:
Average: average = (sum of values)/(total)
Median: arrange a group of numbers in ascending order, and the median is the middle number.
These are just some common mathematical formulas and concepts. With the growth of grade, more mathematical knowledge and formulas will be introduced. It is suggested that according to the specific learning content and teaching materials, we should further understand the mathematical formulas suitable for all grades.