How to Calculate the Circumference of a Circle

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Whenever you are doing manual work like building a fence around a flower bed, or simply solving math problems at school, knowing how to find the circumference of a circle will be very helpful in solving related problems. to this picture.

Table of Contents

Using Diameter

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Write the formula for the circumference of a circle based on the diameter. The simple formula is: C = πd . In this calculation, “C” represents the circumference of the circle and “d” is the diameter. Explained in detail, to find the circumference of a circle, we multiply the meridian by the number pi. Click pi into the calculator for its arithmetic value, which is approximately equal to 3.14.

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Substitute the known path into the formula and solve the problem. For example, the problem is as follows: you have a circular flowerbed with a diameter of 2.4 m, and you want to build a white fence around it at a distance of 1.8 m. To calculate the perimeter of the fence to be erected, first you need to calculate the sum of the diameters of the flowerbed and the fence to be 2.4 m + 1.8 m + 1.8 m. We calculate the diameter as 2.4 m + 1.8 m + 1.8 m = 6 m. Now enter the diameter into the formula and replace π with its arithmetic value:

C = d
C = x 6 m
C = 18.85 m

Using Radius

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Write the formula for the circumference of a circle when the radius is known. The radius of a circle is half the length of the diameter, so the diameter can be interpreted as 2r. Keep that in mind, and you can write a formula for circumference based on a known radius: C = 2πr where “r” is the radius of the circle. Again, use the calculator to determine the arithmetic value of π, which is approximately 3.14.

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Substitute the radius value into the calculation to solve the problem. For example, you want to cut a strip of decorative paper to surround the cake you just made. The radius of the cake is 12.7 cm. To calculate the circumference of the pie, just include the radius in the math:

C = 2πr
C = 2π x 12.7 cm
C = 25.4π
C = 79.8 cm

Advice

You should choose to buy a computer that already has a built-in π key. This will both save you time when typing and give a more accurate answer because the π key will give a more accurate value than using the number 3.14.
To find the circumference when the diameter is known, simply multiply pi by the diameter.
Note: some exercises will require replacing the number pi with another number, like 3.14 or 22/7

Warning

Take it easy when calculating. You know the expression “slowly but surely”?
Remember to always check your work carefully because just one small mistake will pour your effort into the river.
If you find it too difficult, ask a friend, relative or teacher. They will always help you!

Steps

Using Diameter

Using Radius

Advice

Warning

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