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fifty point two four
The circumference of the largest circle in a square is 25.12cm, and the area of the circle is a fraction of the square area,
Diameter = 25.12 / 3.14 = 8cm
Square area = 8 * 8 = 64 cm
Circle area = 4 * 4 * 3.14 = 50.24 cm
50.24/64=157/200
Cut the largest circle in a rectangular paper with a length of 12cm and a width of 10cm. The circumference of the circle is (), and the area is（ Cut the largest circle in a 12 cm long and 10 cm wide rectangular paper. The circumference of the circle is (), and the area is (.)
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Maximum circle diameter = 10 cm
Perimeter = 10 π = 31.4cm
Area = π × 25 = 25 π = 78.5cm2
The circumference of the circle is (10 π cm) and the area is (25 π cm 2)
Cut out the largest circle in a piece of rectangular paper with a length of 12cm and a width of 5cm. How many centimeters is the circumference of this circle? How many circles can you cut?
Cut out the largest circle from a rectangular piece of paper with a length of 12cm and a width of 5cm
The diameter of the largest circle is 5cm. Two such circles can be cut
The circumference of the circle is 3.14x5 = 15.7cm
It is known that the largest circle is cut from a rectangular piece of paper 20 cm long and 12 cm wide. What is the circumference of the circle? What is the area? What is the area of the remaining paper
The circumference of the circle is 3.14 × 12 = 37.68 (CM)
The area is 3.14 × (12 ￣ 2) 2 = 113.04 (square centimeter)
The remaining area is 20 × 12-113.04 = 126.96 (square centimeter)
Ratio of circumference to diameter () ratio ()
The ratio of circumference to diameter of a circle (π: 1) is (π)
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．
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 side length of a square is equal to the diameter of a circle, then the circumference of the square must be greater than that of the circle______ (judge right or wrong)
Let the diameter of the circle be D, then the side length of the square is also d,
Circumference of square: 4D,
The circumference of the circle: 3.14 × d = 3.14 D,
Because 4D > 3.14d,
So the answer is: right
RELATED INFORMATIONS
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- 2. Compare the size of the 18th power of 2 × the 10th power of 3 and the 10th power of 2 × 3 of the 15th power
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- 10. The ratio of () to () of a circle is called PI, which is represented by the letter ()
- 11. If an equilateral triangle is a meter long, its circumference is () meters
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- 14. As shown in FIG. 12, AOB is a straight line, OE bisection of AOC, of bisection of BOD, ∠ cod = 30 ° and try to find the degree of ∠ EOF
- 15. 0
- 16. It is known that in △ ABC, CA = CB, ∠ C = 90 ° D is any point on AB, AE ⊥ CD, perpendicular foot is e, BF ⊥ CD, and vertical foot is F. it is proved that EF = | ae-bf |
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