If you divide 50 into the sum of two prime numbers, you have______ Seed method

If you divide 50 into the sum of two prime numbers, you have______ Seed method

Prime numbers within 50 are: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47; among them, 3 + 47 = 50; 7 + 43 = 50; 13 + 37 = 50; 19 + 31 = 50; answer: there are four different ways to express them

Greek mathematician Diophantine interesting topic: now there are four numbers, take every three of them to add, then the sum is 22, 24, 27 and 20 respectively, find out how many of these four numbers are______ ．

Let the sum of the four numbers be x, then 22 + 24 + 27 + 20 = 3x, x = 31, the four numbers are 31-22 = 9, 31-24 = 7, 31-27 = 4, 31-20 = 11

Greek mathematician Diophantine interesting topic: now there are four numbers, take every three of them to add, then the sum is 22, 24, 27 and 20 respectively, find out how many of these four numbers are______ ．

Let the sum of the four numbers be x, then 22 + 24 + 27 + 20 = 3x, x = 31, the four numbers are 31-22 = 9, 31-24 = 7, 31-27 = 4, 31-20 = 11

There are four numbers, three of which are taken out each time, and the four sums are 22 / 24 / 27 / 20 respectively?
Let the sum of these four numbers be X,

3(a+b+c+d)=22+24+27+20
So a + B + C + D = 31
So the first number is 31-22 = 9
The second number is 31-24 = 7
The third number is 31-27 = 4
The fourth number is 31-20 = 11

Find the perimeter and area of the parallelogram below

Perimeter of parallelogram: (8 + 5) × 2, = 13 × 2, = 26 (CM); area of parallelogram: 8 × 4 = 32 (cm2); answer: perimeter of parallelogram is 26cm; area is 32cm2

Use letters to indicate the area and perimeter of a rectangle, such as a * a
For example, a * B, when a = 10, B = 6

Let the length and width of a rectangle be a and B, respectively
Area s = a * B, perimeter C = 2 (a + b)

The area formula of a rectangle is expressed in letters

a×b=c

The area of a rectangle is 280 square meters. Its length is 70 decimeters. What's its width

A rectangle has an area of 280 square meters. Its length is 70 decimeters. What's its width
B＝s×2÷a

What is the area formula of a rectangle?
Such as the title

Area formula of rectangle = length x width

What is the area formula of a rectangle

Circumference of rectangle = (length + width) × 2
Perimeter of square = side length × 4
Area of rectangle = length × width
Area of a square = side length × side length
Area of triangle = bottom × height △ 2
Area of parallelogram = base × height
Area of trapezoid = (upper bottom + lower bottom) × height △ 2
Diameter = radius × 2 radius = diameter △ 2
Circumference of circle = circumference × diameter=
Circumference × radius × 2
Area of circle = circumference × radius × radius
The surface area of a cuboid=
(L × W + L × H + W × h) × 2
Cuboid volume = length × width × height
The surface area of cube is edge length × edge length × 6
The volume of cube = edge length × edge length × edge length
Side area of cylinder = circumference of bottom circle × height
Surface area of cylinder = area of upper and lower bottom surface + side area
Volume of cylinder = bottom area × height
The volume of the cone = the area of the bottom × the height △ 3
Cuboid (cube, cylinder)
Volume = bottom area × height
Plane figure
Nomenclature perimeter C and area s
Square a - side length C = 4A
S＝a2
Rectangle A and B - side length C = 2 (a + b)
S＝ab
Triangle a, B, C - trilateral length
The height of H-A edge
S - half the circumference
A. B, C - internal angle
Where s = (a + B + C) / 2 s = ah / 2
＝ab/2·sinC
＝[s(s-a)(s-b)(s-c)]1/2
＝a2sinBsinC/(2sinA)
Quadrilateral D, d-diagonal length
α - diagonal angle s = DD / 2 · sin α
A, B-side length of parallelogram
The height of H-A edge
α - angle between two sides s = ah
＝absinα
Diamond A-side length
α - angle
D-Long diagonal length
D-short diagonal length s = DD / 2
＝a2sinα
Trapezoid A and B - length of upper and lower bottom
H-high
M-median line length s = (a + b) H / 2
＝mh
R-radius of circle
D - diameter C = π d = 2 π R
S＝πr2
＝πd2/4
Sector r-sector radius
A-degree of center angle
C＝2r＋2πr×(a/360)
S＝πr2×(a/360)
Arcuate l-arc length
B - chord length
H-vector height
R-radius
The degree of α - center angle s = R2 / 2 · (π α / 180 sin α)
＝r2arccos[(r-h)/r] - (r-h)(2rh-h2)1/2
＝παr2/360 - b/2·[r2-(b/2)2]1/2
＝r(l-b)/2 + bh/2
≈2bh/3
Ring R - radius of outer circle
R - radius of inner circle
D-diameter of outer circle
D-inner diameter s = π (r2-r2)
＝π(D2-d2)/4
D-major axis of ellipse
D-Minor axis s = π DD / 4
Cubic figure
Nomenclature area s and volume V
Cube A-side length s = 6A2
V＝a3
Cuboid a-length
B-width
C-high s = 2 (AB + AC + BC)
V＝abc
Prism S-Base area
H-high v = sh
S-Base area of pyramid
H-high v = SH / 3
S1 and S2 - area of upper and lower base
H-high v = h [S1 + S2 + (s1s1) 1 / 2] / 3
Pseudo cylinder S1 - area of upper and bottom
S2 - bottom area
S0 - middle section area
H-high v = H (S1 + S2 + 4s0) / 6
R-base radius of cylinder
H-high
C-perimeter of bottom surface
S bottom - bottom area
S-side area
S surface - surface area C = 2 π R
S base = π R2
S side = Ch
S table = ch + 2S bottom
V = s, H
＝πr2h
R-radius of hollow cylinder
R - radius of inner circle
H-high v = π H (r2-r2)
R-base radius of straight cone
H-high v = π r2h / 3
R - radius of the top and bottom of the cone
R - bottom radius
H-high v = π H (R2 + RR + R2) / 3
R-radius of sphere
D - diameter v = 4 / 3 π R3 = π D2 / 6
Ball deficiency H - ball deficiency height
R-radius of sphere
A-radius of the ball base v = π H (3a2 + H2) / 6
＝πh2(3r-h)/3
a2＝h(2r-h)
R1 and R2 - the radius of the top and bottom of the table
H-high v = π h [3 (R12 + R22) + H2] / 6
Torus R - radius of torus
D-ring diameter
R-ring section radius
D-ring section diameter v = 2 π 2r2
＝π2Dd2/4
Barrel D - belly diameter
D - bottom diameter
H - barrel height v = π H (2d2 + D2) / 12
(the generatrix is circular and the center of the circle is the center of the barrel)
V＝πh(2D2＋Dd＋3d2/4)/15
(the generatrix is parabolic)