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Take "pi" times the diameter of the circle.

Pi = 3.14159 (ALWAYS)

If circle has a diameter of 10cm, circumference 31.41cm

If circle has a radius of 2inches, the circumference is 12.57 inches. (radius = 2, diameter = 4)

Q: How do you figure out the circumference of a circle?

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The circumference = pi x r2, and the diameter = 2r. So if you start with the circumference, you divide that number by pi (3.1416), then take the square root. What's left is the value of the circle's radius; double it to get the diameter.

My understanding is that as the measurement of the circumference of a circle is derived from an equation using "pi" with pi being an indefinite number, the measurement of the circumference of a circle is also an indefinite number, but the figure can be rounded back to a predetermined number of decimal places.

Assuming you are talking about a circle:* If you know the radius of the circle, multiply that by 2. * If you know the circumference of the circle, divide that by pi. * If you know nothing, you need to measure either the radius, the diameter, or the circumference.

If the diameter of a circle is 69mm then the circumference is: 216.8mm (diameter x pi = circumference).

Consider the straight side as the diameter of a circle, find the circumference of the circle, calculate half the circumference and then add it to the diameter. circumference = pi x diameter = 3.14 x 36 = 113.04 perimeter of semicircle = 1/2 circumference + 36 = 56.52 + 36 = 92.52

Related questions

perimeter or circumference The only answer is perimeter. The circumference is the the perimeter of a circle; the distance around a circle.

Divide the circumference by pi, and that will give you the diameter.

Yes it is because the perimeter describe the outside of the figure, when also the circumference describe the outside of the circle.

The circle's length (or circumference) is determined with the expression C=D(pi).

If the figure is truly a circle, then the circumference is (Radius) x (2 pi) .

The radius of a circle is from the middle to the edge, or half the diameter. The circumference is like the perimeter of the circle, and the formula is pi times the diameter.

Circumference is the enclosing boundary of a curved geometric figure, especially a circle. Radius is a straight line from the center to the circumference of a circle or sphere. Pi is the numerical value of the ratio of the circumference of a circle to its diameter and does not have a circumference or radius of its own.

The perimeter of a circle is its circumference and it found by 2*pi*radius or pi*diameter

the enclosing boundary of a curved geometric figure, esp. a circle. the distance around a circle

Circumference = 2 x {pi} x radius = {pi} x diameter

The distance around a figure is called the "perimeter", unless the figure is a circle - in that case, it is called the "circumference".

r = C /2 pi