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By a 21-inch circle I presume you mean that the diameter is 21 inches. So the radius is half as long, 10.5 inches. The formula for the circumference of a circle is 2 pi r, where r is the radius. Pi is about 3.14. That is accurate to 2 decimals, or 3 significant digits all together. I use that approximation because the dimension we are given has 2 significant digits. So the circumference is pi times the diameter; we multiply 3.14 by 21 inches and get 65.94. To 2 significant digits, that is 66 inches. If you meant that the radius was 21 inches, then the circumference would be twice as much, or 132 inches.
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How do solve circumference?
The circumference of a circle is 2*pi*radius or diameter*pi
How do you get the radius of a circle from the circumfrance?
To find the radius of a circle when given the circumference, you should start with the formula for circumference, which is this: circumference = 2*pi*radius To solve for the radius, you would the have to divide the circumference by 2*pi leaving you with a formula like this: radius = circumference/(2*pi) pi≈3.14159
What name is given to the perimeter of circle?
The perimeter of a circle is its circumference
What is the perimiter of a circle if the circumference?
The perimeter of a circle is its circumference
What is the circumference a circle?
The round perimeter of circle is its circumference
How do solve circumference?
The circumference of a circle is 2*pi*radius or diameter*pi
How do you solve the circumference of a circle?
to find the circumference of a circle, which is the distance in the outside of the circle you need to use the following formula: C=dx 3.14 or circumference equals diameter times pi. The diamater is the length of the circle from end to end. Not very difficult.
What is the diameter of a circle with a 128ft circumference?
The formula for the circumference of a circle is 2*pi*radius or pi*diameter. In this case, it's 128=pi*d. Solve for d, and you get 40.74 feet.
How do you get the radius of a circle from the circumfrance?
To find the radius of a circle when given the circumference, you should start with the formula for circumference, which is this: circumference = 2*pi*radius To solve for the radius, you would the have to divide the circumference by 2*pi leaving you with a formula like this: radius = circumference/(2*pi) pi≈3.14159
What is the circumferenc?
The circumference is the perimeter of a circle. It is used often in mathematics to solve word problems in geometry.
What is the diameter of a circle if the circumference of ten feet?
Circumference=Diameter*pi so plug in 10 = Diameter * pi and solve. I hope you can do this by your self from here
What name is given to the perimeter of circle?
The perimeter of a circle is its circumference
If circle circumference is 255meters find the diameter?
81.2m (approx). 'Pi' (approx 3.142 ) is the quantity that expresses the relationship between the diameter of a circle and its circumference. ie. the circumference is 3.142 times greater than the diameter. To solve your problem, divide 255 metres by 3.142
Who is also circumference of a circle?
Nobody is the circumference of a circle!
What is the perimiter of a circle if the circumference?
The perimeter of a circle is its circumference
What is the circumference a circle?
The round perimeter of circle is its circumference
What is the term for distance around a circle?
The distance around a circle is its circumference
