Number of shares × number of shares = total number of shares ÷ number of shares = number of shares 2, 1 multiple × multiple = multiple1multiple = multiple ÷ multiple = 1 multiple 3, speed × time = distance ÷. Working efficiency × working time = total workload ÷ working efficiency = working time ÷ total workload ÷ working time = working efficiency 6, addend+addend = and-one addend = another addend 7, minuend-subtree = difference minuend-difference = subtree+subtree = minuend 8, factor × factor = Square c perimeter s area a side length perimeter = side length× 4c = 4a area = side length× side length S=a×a 2, cubic v: volume a: side length surface area = side length× side length× 6s table =a×a×6 volume = side length× side length V=a×a×a 3, rectangular c perimeter s area a side length perimeter. × 2s = 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 triangle height = area× 2 ÷ bottom triangle bottom = area× 2 ÷ height 6 parallelogram S area. Bottom area r: bottom radius c: bottom perimeter (1) lateral area = bottom perimeter x height (2) surface area = lateral area+bottom area x 2 (3) volume = bottom area x height (4) volume = lateral area ÷ 2 x radius 10 cone v: volume h: height. Base area r: base radius volume = base area × height ÷3 Total number ÷ Total number = formula (sum+difference) ÷ 2 = large number (sum-difference) ÷ 2 = sum of decimal and multiple problems ÷ (multiple-1) = decimal × multiple. = Decimal Decimal × Multiply = Large number (or Decimal+Difference = Large number) Tree planting problem 1 Tree planting problem on the non-closed line 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 segments+1 = total length ÷ plant spacing-1 total length = plant spacing × (number of plants-1) plant spacing = total length ÷ (then: number of plants = number of nodes-1 = ÷ the difference between the two distributions = the number of shares participating in the distribution meets the problem; Meeting distance = speed, x meeting time = meeting distance; The sum of speed and speed = meeting distance; Meeting time; Problem catching distance = speed difference × catching time = catching distance; Speed difference = catching distance; In-time profit and discount problem profit = selling price ÷ cost-1) × 100% fluctuation amount = principal× fluctuation percentage discount = actual selling price ÷ original selling price× 1 00% (discount <1) interest = principal× interest rate. Length unit conversion 1 km = 1 000m1m =1decimeter1decimeter =10cm/cmha =10000.