Q: How do you find the circumference of a circle with just the radius?

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easy you just double it. Additional answer No, that's incorrect. If you double the radius you get the diameter. To get the circumference you multiply the radius by 2 then by 3.142. 3.142 is known as pi

2 pi rthis is the equation of the circumference of a circle. just multiply out 2 times pi(3.14159) times the radius that you were given.

use the formula pi*diameter = circumference and the formula diameter = 2*radius and combine them 2pi*radius = circumference now you have a formula that you can just plug you numbers into. if you have 3 as your radius, then this is how to find the circumference 2pi*3=circumference 6.28*3=circumference 18.84=circumference

Circumference is equal to 2πr. Where π is equal to 3.14159, so 2π=6.283. Just to find the circumference you are multiplying the radius by a number a little greater than 6.

The radius of any circle is the straight line distance from the centre of the circle to any point on the circumference of the circle. The radius being 21 cm makes no difference to the definition of the radius; it just means that the straight line distance from the centre of that circle is 21cm away from any point on the circumference of that circle. The radius of a circle with a radius of 21 cm is 21 cm.

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Well, isn't that a happy little question! To find the radius of a circle when you know the circumference, you can use the formula: radius = circumference / (2 * Ο). So, if the circumference is 75.36, you can plug that into the formula and find the radius. Just remember, there are no mistakes, just happy little accidents in math!

easy you just double it. Additional answer No, that's incorrect. If you double the radius you get the diameter. To get the circumference you multiply the radius by 2 then by 3.142. 3.142 is known as pi

2 pi rthis is the equation of the circumference of a circle. just multiply out 2 times pi(3.14159) times the radius that you were given.

use the formula pi*diameter = circumference and the formula diameter = 2*radius and combine them 2pi*radius = circumference now you have a formula that you can just plug you numbers into. if you have 3 as your radius, then this is how to find the circumference 2pi*3=circumference 6.28*3=circumference 18.84=circumference

Circumference is equal to 2πr. Where π is equal to 3.14159, so 2π=6.283. Just to find the circumference you are multiplying the radius by a number a little greater than 6.

The process you would use to find the circumference of a circle completely depends on what information you already have about the circle. For example, you might be given the circle's area, or its radius, or its diameter, or the length of one radian of arc along the circumference, and each of those would require a different method to find the circumference. The easiest example is the one where you know the circle's diameter. In that case, simply multiply the diameter by (pi) to get the circumference. The next easiest case is the one where you have the circle's radius ... let's say the radius is 1.5 meters. Knowing that the radius is half of the diameter, you first double the radius, and find that the diameter 3.0 meters. Then you get the circumference just as you did in the first example ... multiply the diameter by (pi). With a radius of 1.5 meter, you would find that the circumference is about 9.425 meters. (rounded)

C = pi d By algebraic rearrangement d = C / pi

The radius of any circle is the straight line distance from the centre of the circle to any point on the circumference of the circle. The radius being 21 cm makes no difference to the definition of the radius; it just means that the straight line distance from the centre of that circle is 21cm away from any point on the circumference of that circle. The radius of a circle with a radius of 21 cm is 21 cm.

You need just a smidgen of algebra.The area of any circle is (pi) x (radius)2 .For this circle, you know that (pi) x (radius)2 = 49.You can massgae this around to find the radius, and thenthe circumference is just (2 pi) x (radius).If you need it all in one step, then Circumference= 2 x sqrt(pi x Area) ,but the other way is easier for me, because I don't have to memorizeanother formula. I find deriving easier than memorizing..

Oh, dude, you just gotta divide the circumference by 2Ο to find the radius. So, like, 11.304 divided by 2Ο is about 1.8. So, the radius of the circle is approximately 1.8. Easy peasy, right?

You would have to know the length of the radius. The center of the circle is at one end of the radius. If you just know where some part of the radius is, and not that the part touches the circle then you cannot know where the center is without at lest a point on the circumference.

Just divide the circumference by (2 x pi). Pi is about 3.1416.