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 meters

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 rectangle

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 (L× W+L× H+W× H) ×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=2∏r

(2) area = radius × radius×∈

Cylinder 9

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

Total number ÷ Total number of copies = average value

Formula of sum and difference problem

(sum+difference) ÷ 2 = large number

(sum and difference) ÷ 2 = decimal

And folding problems.

Sum \ (multiple-1) = decimal

Decimal × multiple = large number

(or sum-decimal = large number)

Difference problem

Difference ÷ (multiple-1) = decimal

Decimal × multiple = large number

(or decimal+difference = large number)

Tree planting problem

1 The problem of planting trees on unclosed lines can be 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)

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)

The quantitative relationship of planting trees 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

The question of profit and loss

(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.

encounter a problem

Meeting distance = speed × meeting time

Meeting time = meeting distance/speed and

Speed Sum = Meeting Distance/Meeting Time

Catch up with the problem

Catch-up distance = speed difference× catch-up time

Catch-up time = catch-up distance ÷ speed difference

Speed difference = catching distance ÷ catching time

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

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.

Profit and discount problem

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× 1 00% (discount <1)

Interest = principal × interest rate× time

After-tax interest = principal × interest rate× congruent triangles

together

Corner edge

Corner corner

Aas congruence law

Hypotenuse right angle edge

The corresponding edges of congruent triangles are equal, and the corresponding angles are equal.

Axial symmetry

isosceles triangle

Three lines in one

equilateral triangle

Real numbers have nothing to say.

linear function

y=kx

y=kx+b

(a+b)2=a2+2ab+b2

(a-b)2=a2-2ab+b2

(a+b)(a-b)=a2-b2