Total copies/copies = copies?
2. 1 multiple × multiple = multiple ÷ 1 multiple = multiple?
What multiple/multiple = 1 multiple?
3. Speed × time = distance/speed = time
Distance ÷ time = speed?
4. Unit price × quantity = total price/unit price = quantity
Total price ÷ quantity = unit price?
5. Work efficiency × working time = total workload.
? Total amount of work ÷ work efficiency = working hours
Total amount of work ÷ working time = working efficiency?
6. Appendix+Appendix = and? And-one addend = another addend?
7. Minus-Minus = Difference Minus-Difference = Minus?
Difference+subtraction = subtraction?
8. Factor × factor = product? Product ÷ One factor = another factor?
9. Divider Divider = quotient? Dividend quotient = divisor?
Quotient × Divider = Divider?
Calculation formula of mathematical graphics in primary schools
1, squared: c perimeter s area a side length?
Perimeter = side length ×4C=4a
Area = side length × side length S=a×a?
2. Cube: V: Volume A: Side length
Surface area = side length× side length× 6?
S table =a×a×6
Volume = side length x side length x side length? V=a×a×a？
3. rectangle: c perimeter, s area, and a side length.
Circumference = (length+width) ×2C=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. What is the height of the area A and the base H of the triangle?
Area = bottom × height ÷2s=ah÷2?
Height of triangle = area × 2 bottom?
Triangle base = area ×2÷ height?
6. parallelogram: s area, a base and h height
Area = bottom × height? S = huh?
7. trapezoid: s area a, upper bottom b, lower bottom h?
Area = (upper bottom+lower bottom) × height ÷2 s=(a+b)×h÷2?
8. circle: s plane c circumference? ∏? D= diameter r= radius?
(1) circumference = diameter ×∏ = 2×∏× radius? C=∏d=2∏r？
(2) area = radius × radius× ∏?
9. cylinder: v: volume h: height s: bottom area r: bottom radius
C: bottom circumference?
(1) Side area = bottom perimeter × 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 high? S bottom area r bottom radius?
Volume = bottom area × height ÷3?
Total number ÷ Total number of copies = average?
Formula of sum and difference problem?
(sum+difference) ÷ 2 = large number? (sum and difference) ÷ 2 = decimal?
And times the problem?
And ÷ (multiple-1) = decimal × multiple = large number?
(or sum-decimal = large number)?
Difference problem?
Difference ÷ (multiple-1) = decimal × multiple = large number?
(or decimal+difference = large number)?
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)?
(2) If trees are planted at one end of the non-closed line, but not at the other end, then:
Number of plants = number of nodes = 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 quantitative relationship of planting trees on the closed line is as follows?
Number of plants = number of nodes = total length ÷ plant spacing?
Total length = plant spacing × number of plants? Plant spacing = total length ÷ number of plants?
Profit and loss problem?
(profit+loss) ÷ Difference between two distributions = number of shares participating in distribution?
(Daying-Xiaoying) ÷ The difference between the two distributions = the number of shares participating in the distribution?
(big loss-small loss) ÷ Difference between two distributions = number of shares participating in distribution?
Have a problem?
Meeting distance = speed and × 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?
Running water problem?
Downstream velocity = still velocity+current velocity?
Countercurrent velocity = still water velocity-current velocity?
Static water velocity = (downstream velocity+countercurrent velocity) ÷2?
Water velocity = (downstream velocity-countercurrent velocity) ÷2?
Focus on the problem?
Solute weight+solvent weight = solution weight?
The weight of solute/solution × 100% = concentration?
Solution weight × concentration = solute weight?
Weight-concentration of solute = weight of solution?
Profit and discount?
Profit = selling price-cost?
Profit rate = profit/cost × 100% = (selling price/cost-1) × 100%?
Increase or decrease amount = principal × increase or decrease percentage?
Discount = actual selling price ÷ original selling price × 100% (discount < 1)?
Interest = principal x interest rate x time?
After-tax interest = principal × interest rate× time × (1-20%)?
Length unit conversion?
1 km =1000m1m =10 decimeter1decimeter = 10cm.
1 m = 100 cm？ 1 cm = 10 mm？
Area unit conversion?
1 km2 = 100 hectare? 1 ha =10000m2?
1 m2 = 100 square decimeter 1 square decimeter = 100 square centimeter?
1 cm2 = 100 mm2？
Volume (volume) unit conversion?
1 m3 = 1000 cubic decimeter? 1 cubic decimeter = 1000 cubic centimeter?
1 cubic decimeter = 1 liter 1 cubic centimeter = 1 ml?
1 m3 = 1000 liter?
Weight unit conversion?
1 ton = 1000 kg? 1 kg = 1000 g？ 1 kg = 1 kg?
RMB unit conversion?
1 yuan = 10 angle? 1 angle = 10 minute? 1 yuan = 100 integral?
Time unit conversion?
1 century = 100 year? 1 year = 65438+ February?
Da Yue (3 1 day) has:? 1\ 3 \ 5 \ 7 \ 8 \10 \ 65438+February?
Abortion (30 days) has:? April \ June \ September \ 165438+ October?
February 28th, normal year? February 29th of leap year?
365 days in a normal year and 366 days in a leap year?
1 day =24 hours 1 hour =60 minutes
1 minute =60 seconds 1 hour =3600 seconds?
What is the formula for calculating the perimeter, area and volume of mathematical geometry in primary schools?
1, the perimeter of the rectangle = (length+width× 2? C=(a+b)×2？
2. The circumference of a square = side length ×4C=4a?
3. Area of rectangle = length× width S=ab?
4. Area of a square = side length × side length S=a.a= a?
5. Area of triangle = base × height ÷2? S=ah÷2？
6. Area of parallelogram = base × height S=ah?
7. Trapezoidal area = (upper bottom+lower bottom) × height ÷2
S=(a+b)h÷2？
8. Diameter = radius ×2? d=2r？
Radius = diameter ÷2r= d÷2?
9. The circumference of a circle = π× diameter = π× radius× 2?
c=πd =2πr？
10, circular area = pi × radius× radius?
The number of changes
Map distance/actual distance = scale
Distance on the map = scale × actual distance
Actual distance = distance on map/scale.
Proportional relation x/y=k (certain)
Inverse relationship x.y=k (definite)