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The ratio of a circle's circumference to its area is called the reciprocal of half the radius. The ratio of the circumference to its radius is called two times pi.
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Why is pi used to measure circles?
Pi is the ratio of the circumference ( the perimeter) of a circle to its diameter. You might have learned in school that if C is the circumference of the circle., then C=2Pir or C=pixd from which we say pi = C/d or the ratio of the circumference of the circle to its diameter. This has been known since ancient times! William Jones gave us the symbol we currently use for it. This comes from the 16th letter in the Greek alphabet. So we use it to measure circles because of what it is.
How is pi used to find circumference of circles?
Pi times the diameter of a circle gives its circumference.
The ratio of the circumference of a circle to its diameter roughly equal to 3.141592?
Circumference (C) = diameter (D) times pi (3.141592) is the ratio of the circumference of a circle to its diameter.
What is 3.1425?
That is called pi, the ratio between the diameter and the circumference of a circle. Of course, 3.14159265 is more accurate.
Do two circles have the same circumference if they have the same diameter?
Yes.
What is the ratio to any circles circumference to the diameter?
The ratio of the circumference of a circle to its diameter is Pi. (3.14159)
Is the ratio of the circumference to the diameter is constant for any circles?
Yes, pi.
Is the ratio of circumference to the diameter of all circles always the same?
Yes
What did early civilizations notice about the ratio of circumference to diameter?
They noticed circumference/diameter was a constant ratio applicable to all circles no matter whattheir sizes were
What can you say about the ratio of circumference to the diameter of the circles?
For any size circle, the ratio of the circumference to the diameter is constant. This constant is known as pi, an irrational number which is approximately equal to 3.1416.Since the Circumference is pi times Diameter. (C=πD)Therefore the ratio of Circumference to Diameter is π:1.
If the areas of two circles are 48 and 75 find the ratio of their circumferences?
48 works out as a circumference of 24.5597207 units 75 works out as a circumference of 30.69980124 units So the ratio is about 4:5
What is a part of the circumference of a circle called?
Circumference is a special name for a circles perimeter. I think the answer you are looking for is radious.
What is the ratio of PI circles?
In a circle Pi it the ratio of the circumference to the diameter. That is to say, if C is the cirumference and D is the diamter of any circle, we have: Pi=C/D
Who discovered circumference of circle?
The ancient Greek mathematician Pythagoras is usually creditted for the discovery of the ratio of circumference to radius of circles. That is, Circumference = 2 * Pi * Radius. The number Pi represents (3.1415....) is named after him.
Why does the Greek letter Pi signify the ratio of a circles circumference?
The Greek word for perimeter begins with the letter pi, and since circumference and perimeter are the same the letter Pi was used.
Why are the equator and all lines of longitude called great circles?
The equator and all lines of longitude are called great circles because the represent the circumference of the earth. The other latitude lines along the globe are smaller then the actually circumference.
What is the number called that is the ratio of the circumference and diameter of a circle?
It is pi
