An equilateral triangle has a circumference of 2.4 decimeters and a height of 0.6 decimeters. Its area is () decimeters

An equilateral triangle has a circumference of 2.4 decimeters and a height of 0.6 decimeters. Its area is () decimeters

An equilateral triangle has a circumference of 2.4 decimeters and a height of 0.6 decimeters. Its area is (0.24) square decimeters
Side length = 2.4 / 3 = 0.8 decimeter
Area = 0.8x0.6/2 = 0.24 square decimeter

An equilateral triangle, the side length is a decimeter, how many decimeters is its circumference?

3A

The circumference of the circle in the figure below is 25.12cm. Calculate the area of the figure

The radius of the circle is:
25.12÷3.14÷2，
=8÷2，
=4 (CM);
The area of the circle is 3.14 × 42
=3.14×16，
=24 (square centimeter);
Answer: the area of figure is 50.24 square centimeter

The circumference of a circle is 25.12m, and its area is______ .

Radius: 25.12 △ 3.14 △ 2 = 4 (m),
Area: 3.14 × 42 = 50.24 (M2);
A: its area is 50.24 square meters
So the answer is: 50.24 square meters

The area of the circle in the figure is equal to that of the rectangle. The circumference of the circle is 25.12cm, and the perimeter of the shadow part is______ .

Perimeter of shadow part: 25.12 × 5
4 = 31.4 (CM);
A: the perimeter of the shadow part is 31.4cm
So the answer is: 31.4 cm

A rectangular paper is 12 cm long and 8 cm wide. Cut the largest circle in this rectangular paper. The area of the circle is () A. 113.04 square centimeter B. 50.24 square centimeter C. 96 square centimeter D. 45.76 square centimeter

The diameter of the circle is 8 cm;
Area of circle: 3.14 × (8 △ 2) 2,
=3.14×16，
=24 (square centimeter);
A: the area of this circle is 50.24 square centimeters
Therefore, B

1. The ratio of circumference to side length of square is () and the ratio is (); the ratio of circumference to diameter of circle is (); the ratio of radius to perimeter of element is (); the ratio of diameter to radius of circle is (); the ratio of diameter to radius of circle is () 2. The radius of the big and small circles is 2cm and 3cm respectively, and the perimeter ratio of the two circles is (); the area ratio of the two circles is () 3. The number of black rabbits is two fifths of that of white rabbits, so the ratio of black rabbits to white rabbits is (), and the ratio of white rabbits to black rabbits is (). What percentage of black rabbits accounts for the total number of rabbits? 4. The number of grey rabbits is one fifth less than that of white rabbits, so the ratio of grey rabbits to white rabbits is (); what percentage of grey rabbits are white rabbits? 5. The ratio of the three inner angles of the two triangular plates is () and ()

1. The ratio of square circumference to side length is (4:1), the ratio is (4); the ratio of circumference to diameter of circle is (π: 1), the ratio is (π); the ratio of radius to perimeter of element is (1:2 π), the ratio is (1 / 2 π); the ratio of diameter to radius of circle is (2:1), the ratio is (2) 2

The ratio of the side length to the circumference of a square is______ The ratio of the circumference of a circle to its diameter is______ .

(1) Side length of square: perimeter = 1:4 = 1 △ 4 = 1
4；
(2) Circumference of a circle: its diameter = π: 1 = π
So the answer is: 1
4，π．

If the circumference of a square is equal to that of a circle, then the side length of the square is greater than the diameter of the circle A. Long B. short C. same length D. not sure

∵ perimeter of square 4A = 2 π R
∴r=2a/π
Side length of square = a
ν circle diameter = 4A / π
∵4>π
∴4a/π>a
ν select B

Perimeter and side growth of square______ The circumference of a circle is related to its diameter______ .

The perimeter of the square △ side length = 4 (certain),
So the perimeter of a square is in positive proportion to its side length;
Because: the circumference of the circle △ diameter = pi (certain),
So the circumference of the circle is proportional to its diameter;
So the answer is: positive proportion, positive proportion