1. Each copy × number of copies = total.
Total copies/number of copies = number of copies
Total copies/number of copies = number of copies
2. 1 multiple× multiple = multiple
Multiply1Multiply = Multiply
Multiply/Multiply = 1 Multiply
3. Speed × time = distance
Distance/speed = time
Distance/time = speed
4. Unit price × quantity = total price
Total price/unit price = quantity
Total price ÷ quantity = unit price
5. Work efficiency × working hours = total workload.
Total amount of work ÷ work efficiency = working hours
Total workload ÷ working time = working efficiency
6 addend+addend = sum
And-one addend = another addend
7 minuend-minuend = difference
Negative difference = negative
Difference+Minus = Minus
8 factor × factor = product
Product ÷ One factor = another factor
Dividend = quotient
Dividend = divisor
Quotient × Divider = Divider
Calculation formula of mathematical graphics in primary schools
1. square
Perimeter area side length
Perimeter = side length ×4
1/5
C=4a
Area = side length × side length
S=a×a
2. Cubic
Volume a: edge length
Surface area = side length × side length ×6
S table =a×a×6
Volume = side length × side length × side length
V=a×a×a
3. Rectangular shape
Perimeter area side length
Circumference = (length+width) ×2
C=2(a+b)
Area = length × width
S=ab
4. Cuboid
V: volume s: area a: length b: width h: height.
(1) surface area = (length× width+length× height+width× height) ×2
S=2(ab+ah+bh)
(2) Volume = length × width × height
V=abh
5. Triangle
S area a bottom h height
Area = bottom × height ÷2
s=ah÷2
Height of triangle = area ×2÷ base.
Triangle base = area ×2÷ height
6. Parallelogram
S area a bottom h height
Area = bottom × height
S = ah
7. trapezoid
Height of upper bottom b and lower bottom h in s area a
Area = (upper bottom+lower bottom) × height ÷2