Square and circle of equal circumference______ It has a large area

Square and circle of equal circumference______ It has a large area

Among all figures with equal perimeter, the circle has the largest area

Know the area of rectangle, square, circle, how to calculate perimeter?

A circle or a square is OK. A rectangle only knows its area, but it can't work out its unique perimeter. It has to have a known quantity to work out its unique perimeter,
Two known conditions are required, but the minimum perimeter can be obtained

Whose area is bigger, circle, square or rectangle

Circle area > square area > rectangle area
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Let the circumference be C, the radius of the circle be r, the side length of the square be a, the length of the square be x, and the width be y
[for circles]
C=2πR ,R=C/2π
Area of circle = π R & # 178; = π (C / 2 π) &# 178; = C & # 178 / 4 π = C & # 178 / 12.56 (π = 3.14)
[for square]
C=4a,a=C/4
Area of square = A & # 178; = (C / 4) &# 178; = C & # 178 / 16
[for rectangle]
C=2(x+y),x=C/2-y.
Rectangle area = xy = (C / 2-y) y = YC / 2-y & # 178; = (y-c / 4) &# 178; + C / 4
When y-c / 4 = 0, that is, y = C / 4, the area of rectangle is the largest, which is C / 4
At this point, the figure is actually a square
So square area > rectangle area
Compare the area of a circle C & # 178 / 12.56 with that of a square C & # 178 / 16
Obviously, C & # 178 / 12.56 > C & # 178 / 16
So the area of circle > square > rectangle

In π 0.33 18 22 / 7 3.1416 0 2001 - 3 / 5 - 0.142857 95%, there are () positive numbers and () negative numbers
There are () integers, () fractions and () rational numbers

In π 0.33 18 22 / 7 3.1416 0 2001 - 3 / 5 - 0.142857 95%, there are (7) positive numbers, (2) negative numbers, (3) integers, (3) fractions and (9) rational numbers

7,-9.24,-301,31,25,0,22/7,-18,3.1416,2014,-3/5,-0.14287,67%
Integer, positive integer, coarse integer, positive fraction, negative fraction

Integers: 7, - 301,31,25,0, - 182014287
Positive integer: 7,31,252014287
Negative integers: - 301, - 18
Positive score: 22 / 7,3.1416,67%
Negative fraction: - 9.24, - 3 / 5, - 0.14

Will 0.01 09 fill in 9 circles to make the number of each side equal

0.08 0.03 0.04
0.01 0.05 0.09
0.06 0.07 0.02

24 △ 1.5-8.4 × 0.251 + 0.45 △ 0.9-8 / 7 (4 / 5-2 / 3) x = 120.4x + 4 × 1.7 = 16.8
24 △ 1.5-8.4 × 0.251 + 0.45 △ 0.9-8 / 7 (4 / 5-2 / 3) x = 12
0.4X+4×1.7=16.8

24÷1.5-8.4×0.25=16-2.1*（4*0.25）= 16-2.1=13.9 1+0.45÷0.9-7/8=1+0.5-0.875=0.625 （4/5-2/3）X=12（12/15-10/15）x=12 2/15x=12 x=90 0.4X+4×1.7=16.8 0.4x+6.8=16.8 0.4x=10 x=25

(6 / 5 + 9 / 11 + 1 and 5 / 7) / (3 / 11 + 2 / 5 + 4 / 7) simple calculation

(6 / 5 + 9 / 11 + 1 and 5 / 7) / (3 / 11 + 2 / 5 + 4 / 7)
= (9/11+6/5+12/7)/(3/11+2/5+4/7)
=3x(3/11+2/5+4/7)/(3/11+2/5+4/7)
=3

2 / 3 × 5 / 7 + 2 / 3 × 2 / 7 (simple calculation) 3 / 4 × 1 / 9 + 1 / 4 △ 9 (simple calculation) 5 - (6 / 7 △ 9)
2 / 3 × 5 / 7 + 2 / 3 × 2 / 7 (simple calculation)
3 / 4 × 1 / 9 + 1 / 4 △ 9 (simple calculation)
5 - (6 / 7 △ 3 / 14 + 3 / 16) (simple calculation)

1#
2/3(5/7+2/7)
=2/3
2#
3/4*1/9+1/4*1/9
=(3/4+1/4)*1/9
=1/9
3#
5-(6/7*14/3+3/16)
=5-4-3/16
=13/16

(7.2 × 3.8) / (3.6 × 1.9) simple calculation

(7.2×3.8)÷(3.6×1.9)
=（7.2÷3.6）×（3.8÷1.9）
=2×2
=4