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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.
If the area of a circle is 201.06 then the circumference of the circle is?
The formula to find the circumference of a circle is C = 2πr, where r is the radius of the circle. To find the circumference, you first need to find the radius by using the formula for the area of a circle (A = πr^2). Given that the area is 201.06, you can solve for the radius. Once you have the radius, you can plug it into the formula C = 2πr to find the circumference.
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 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 is the circumferenc?
The circumference is the distance around a circle or any closed curve. It is calculated by multiplying the diameter of the circle by π (pi), approximately equal to 3.14159.
Define what the circumference of a circle?
The circumference of a circle is the perimeter of the circle for a given diamater.
What is the area of a circle with circumference 9.42?
The formula for the circumference of a circle is 2πr, where r is the radius. We can rearrange this formula to solve for the radius: r = circumference / (2π) = 9.42 / (2 * 3.14159) = 1.5. Then, using the formula for the area of a circle (πr^2), the area is π * 1.5^2 ≈ 7.07 square units.
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
What name is given to the perimeter of circle?
The perimeter of a circle is its circumference
Who is also circumference of a circle?
Nobody is the circumference of a circle!
