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
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
s=(a+b)×h÷2
8 laps
Area c perimeter d= diameter r= radius
(1) circumference = diameter ×∏=2×∏× radius
c =∏d = 2r
(2) area = radius × radius×∈
9. Cylinder
V: volume h: height s; Bottom area r: bottom radius c: bottom perimeter
(1) lateral area = bottom circumference × height.
(2) Surface area = lateral area+bottom area ×2
(3) Volume = bottom area × height
(4) Volume = lateral area ÷2× radius.
10. Cone
V: volume h: height s; Bottom area r: bottom radius
Volume = bottom area × height ÷3
1 1. Formula of sum and difference problem
Total number ÷ Total number of copies = average value
(sum+difference) ÷2= large number
(sum and difference) ÷2= decimal
12. Sum times problem
Sum \ (multiple-1)= decimal
Decimal × multiple = large number
(or sum-decimal = large number)
13. Differential time problem
Difference ÷ (multiple-1)= decimal
Decimal × multiple = large number
(or decimal+difference = large number)
14. Planting trees:
1) The problem of planting trees on unclosed lines can be mainly divided into the following three situations:
(1) If trees are planted at both ends of the non-closed line, then:
Number of plants = number of nodes+1= total length-1.
Total length = plant spacing × (number of plants-1)
Plant spacing = total length ÷ (number of plants-1)#p# Subtitle #e#
2 If you want to plant trees at one end of the unclosed line and not at the other end, then:
Number of plants = number of segments = total length ÷ plant spacing
Total length = plant spacing × number of plants
Plant spacing = total length/number of plants
(3) If no trees are planted at both ends of the non-closed line, then:
Number of plants = number of nodes-1= total length-1.
Total length = plant spacing × (number of plants+1)
Plant spacing = total length ÷ (number of plants+1)
2) The relationship between the number of trees planted on the closed line is as follows
Number of plants = number of segments = total length ÷ plant spacing
Total length = plant spacing × number of plants
Plant spacing = total length/number of plants
15 profit and loss problem:
(Profit+Loss) ÷ Difference between two distributions = number of shares participating in distribution.
(Big profit-small profit) ÷ Difference between two distributions = number of shares participating in distribution.
(big loss-small loss) ÷ The difference between two distributions = the number of shares participating in the distribution.
16. Meeting questions:
Meeting distance = speed × meeting time
Meeting time = meeting distance/speed and
Speed Sum = Meeting Distance/Meeting Time
17. Follow-up questions:
Catch-up distance = speed difference× catch-up time
Catch-up time = catch-up distance ÷ speed difference
Speed difference = catching distance ÷ catching time
18. tap water problem:
Downstream velocity = still water velocity+current velocity
Countercurrent velocity = still water velocity-current velocity
Still water velocity = (downstream velocity+countercurrent velocity) ÷2
Water velocity = (downstream velocity-countercurrent velocity) ÷2
19. concentration problem:
Solute weight+solvent weight = solution weight.
The weight of solute/solution × 100%= concentration.
Solution weight × concentration = solute weight
Solute weight-concentration = solution weight.
20. Profits and discounts:
Profit = selling price-cost
Profit rate = profit/cost × 100%= (selling price/cost-1)× 100%.
Up and down amount = principal × up and down percentage
Discount = actual selling price/original selling price × 100% (discount
Interest = principal × interest rate× time
After-tax interest = principal × interest rate × time ×( 1-20%)