How to find diameter from circumferenceApr 10, 2022 · Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm. Generally, the diameter is used to calculate the circumference, therefore, it is also possible to calculate the length of the diameter if we have the circumference The formula for the circumference is: where, C is the length of the circumference and π is a mathematical constant that has an approximate value of 3.1416. Circumference to Diameter Calculator. This circumference to diameter calculator is used to find the diameter of a circle given its circumference. Just enter the value of the circumference. Then tap or click the Calculate button. Get the result. You can also select units of measure for both input data and results. The diameter of a circle will be shown in the selected units. Apr 10, 2022 · Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm. Because circumference is related to diameter, we can use that ratio to find a missing value. Suppose you know the diameter of a circle but need to find its circumference. Circumference, C, can be placed in a ratio with diameter, d, with the answer pi, π. We can rewrite that relationship: C/ d = π. C = π x d. C = π d.o Diameter. o Circumference. o Pi (π). Objectives. o Identify some basic parts of a circle Again, in each case, the circumference is slightly more than three times the diameter of the circle. Thus, using this known value of the circumference, we can calculate the radius and use it to find the area.Circumference to Diameter Formula To Find & Convert. How. To calculate the diameter of a circle with circumference 1 cm, use the formla of C = πd, or d = C/π, where C is the circumference and d is the diameter.In this video you will learn how to work out the diameter of a circle from its circumfernce. You can do this in one step by dividing the circumfernce by Pi. ...How to Calculate Circumference from Diameter. Rosemary Njeri. Circumference is the distance around a circle. That is, the circumference would be the length of the circle if it were opened up and straightened out to a line segment. Diameter is a chord or a line segment that runs through the center point of any circle and touches two points on ...The circumference of the circle having a diameter of 8 feet is calculated using the equation: C= 2⋅π⋅r C = 2 ⋅ π ⋅ r. where. C C is the circumference, r = 8 ft 2 = 4 f t r = 8 f t 2 = 4 ... Calculating the diameter using the circumference is now as easy as 1-2-3! Simply divide the circumference by 3.14 (value of π) and round your answer to the nearest tenth. Furnished with answer key, our pdf calculate diameter from circumference worksheets are available in customary and metric units.how to find radius from circumference. In addition to the radius, there is also the diameter. The diameter is twice as large as the radius. The formula looks like this: d = 2 * r. For example, if the radius of a circle is 2 meters, then the diameter is 4 meters. In addition, the so-called circle number π (pronounced: pi) is required.fortnite bucks fortnite v bucks storesWe have another article which describes how to measure rims for spokes. What size tire do you need to buy for your bicycle? There are so many different tire sizes and different systems for marking tire sizes that have been used over the years that this You derive the diameter from the circumference.How to Calculate Diameter From Circumference Sciencing. Economy. Details: The distance around the edge of the circle is called the circumference. › Get more: Use circumference to find diameterView Economy. Circumference to Diameter Formula To Find & Convert.The radius, the diameter, and the circumference are the three defining aspects of every circle. Given the radius or diameter and pi you can calculate the circumference. The diameter is the distance from one side of the circle to the other at its widest points. The diameter will always pass through the center of the circle.Calculate the radius, diameter, circumference, or area of a circle, and learn the formulas and steps to solve each dimension of a circle. Circle Calculator - Find Radius, Circumference, & Area.How big is Earth? Find out here. Radius, diameter and circumference. Density, mass and volume. Highest and lowest points. Earth, the third planet from the sun, is the fifth-largest planet in the solar system; only the gas giants Jupiter, Saturn, Uranus and Neptune are bigger.How To Find Circumference From Diameter Guide. You can also select units of measure for both input data and results.This circumference to diameter calculator is used to find the diameter of a circle given its circumference.That is to say, you can find the circumference of a circle just by multiplying the diameter by pi. The circumference of the circle having a diameter of 8 feet is calculated using the equation: C= 2⋅π⋅r C = 2 ⋅ π ⋅ r. where. C C is the circumference, r = 8 ft 2 = 4 f t r = 8 f t 2 = 4 ... In this tutorial, we will learn to create a C program that will Find the Diameter, Circumference, and Area of a Circle in C programming.Finding the diameter using the circumference Formula for the diameter using the circumference. To calculate the length of the diameter of circles, we can use both... Diameter using the circumference and radius – Examples with answers. The formulas for the diameter of circles are... Finding the ... , The diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circumference of the circle. Use the midpoint formula to find the midpoint of the line segment. Substitute in the values for.Formula The formula used to calculate the circle diameter is: ø = C / π Symbols ø = Circle diameter C = Circle circumference π = Pi = 3.14159… Circumference of Circle Enter the circumference which is the total length of the edge around the circle, if it was straightened out. Diameter of Circle Circumference of a circle. The circumference is the distance around a circle (its perimeter!): Created with Raphaël. Here are two circles with their circumference and diameter labeled: Created with Raphaël. Let's look at the ratio of the circumference to diameter of each circle: Circle 1. Circle 2.oblong pill pIn this C++ program, we will calculate circumference and area of circle given radius of the circle. The area of circle is the amount of two-dimensional Then we calculate the area of circle using above mentioned formulae and print it on screen using cout. C++ Program to Find Circumference of Circle.This tool will calculate the diameter of a circle from the circumference, and will convert different measurement units for circumference and diameter. Formula. The formula used to calculate the circle diameter is: ø = C / π. Symbols. ø = Circle diameter; C = Circle circumference; π = Pi = 3.14159… Circumference of CircleHow do you find the diameter from the circumference? You cannot find the diameter of something from its circumference unless it is a circle and, in that case, diameter = circumference/pi. To find diameter, divide circumference by pi.The straight from any point to another through the the center point is called the diameter. K-12 students may refer the below formulas of circle to know what are all the input parameters are being used to find the area, perimeter or radius of a circle. Formula to calculate area, circumference, diameter & radius of a circle If you know the diameter of the circle and would like to calculate the area, circumference, and radius, enter the diameter in the field on this line. Enter only digits 0-9 and a decimal point (if applicable). Non-numeric characters will not compute. Or, tap the plus (+) to expand the mini calculator if you need to find the diameter. Circles on ACT math test your knowledge of radii, circumferences, areas, and more. Learn important circle formulas and strategies and practice on real math problems here. This will be your complete guide to ACT circles, including areas, circumferences, degrees, arcs, and points on a circle.Practice Problem: Find the area and circumference of a circle with a diameter of 4 inches. Solution: One of the first rules of solving these types of problems involving circles is to carefully note whether we are dealing with the radius or the diameter. In this problem, the circle is described using the diameter, which is 4 inches. Calculating the diameter using the circumference is now as easy as 1-2-3! Simply divide the circumference by 3.14 (value of π) and round your answer to the nearest tenth. Furnished with answer key, our pdf calculate diameter from circumference worksheets are available in customary and metric units.Getting Diameter from Circumference Since we know circumference and diameter are related by π, we can use π to find diameter if we know circumference. We do a bit of mathematics to isolate diameter, d, on one side of the equation: C = π d C/π = d Dividing the circumference by π, then, will give us the diameter. The purpose of this calculator demonstration is to use PI and the circumference of a circle to find the diameter of that circle. To use this calculator, begin by entering the circumference of a given circle and PI. Click on the "Calculate" button for the returned calculated value of the dimeter, thus proving it. how to find radius from circumference. In addition to the radius, there is also the diameter. The diameter is twice as large as the radius. The formula looks like this: d = 2 * r. For example, if the radius of a circle is 2 meters, then the diameter is 4 meters. In addition, the so-called circle number π (pronounced: pi) is required.python pool mapIn this C++ program, we will calculate circumference and area of circle given radius of the circle. The area of circle is the amount of two-dimensional Then we calculate the area of circle using above mentioned formulae and print it on screen using cout. C++ Program to Find Circumference of Circle.If the circumference of a circle is known then we can easily find the value of the diameter by substituting the values in the formula: Diameter = C ÷ π; where 'C' is the circumference and the value of π is 22/7 or 3.14 approximately.Apr 10, 2022 · Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm. These cookies allow us to count visits, identify traffic sources and understand how our services are used to measure and improve performance. If you do not allow these cookies, we will not know when you visited our site and we will not be able to monitor its performance.Calculate the radius, diameter, circumference, or area of a circle, and learn the formulas and steps to solve each dimension of a circle. Circle Calculator - Find Radius, Circumference, & Area.Half of the diameter, or the distance from the midpoint to the circle border, is called the radius of the circle (r). The circumference of a circle is found using this formulaApr 10, 2022 · Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm. How big is Earth? Find out here. Radius, diameter and circumference. Density, mass and volume. Highest and lowest points. Earth, the third planet from the sun, is the fifth-largest planet in the solar system; only the gas giants Jupiter, Saturn, Uranus and Neptune are bigger.In this C++ program, we will calculate circumference and area of circle given radius of the circle. The area of circle is the amount of two-dimensional Then we calculate the area of circle using above mentioned formulae and print it on screen using cout. C++ Program to Find Circumference of Circle.How To Find The Circumference Of Any Diameter Fig. 1. From the centre C describe a circle A B, haying the required diameter ; then place the corner of the square at the centre 0, and draw the lines C D and C E ; then draw the chord D E: three times the diameter added to the distance from the middle of the chord D F E to the middle of the ... If you have the diameter measurement, multiply it by pi to find the circumference. For example, a wheel with a 10-inch diameter will have a circumference of 10 x 3.14, or 31.4 inches. To calculate using the radius, multiply the radius by 2 and then multiply that result by pi.In this C++ program, we will calculate circumference and area of circle given radius of the circle. The area of circle is the amount of two-dimensional Then we calculate the area of circle using above mentioned formulae and print it on screen using cout. C++ Program to Find Circumference of Circle.one eleven grillFind the exact circumference of eSolutions M. anual - Powered by Cognero. 10. Name the center of the circle. SOLUTION: R. SOLUTION: The circumference C of a circle with diameter d is given by Here, C = 124 ft. Use the formula to find the diameter.If you have the diameter measurement, multiply it by pi to find the circumference. For example, a wheel with a 10-inch diameter will have a circumference of 10 x 3.14, or 31.4 inches. To calculate using the radius, multiply the radius by 2 and then multiply that result by pi.This tool will calculate the circumference of a circle from the diameter, and will convert different measurement units for diameter and circumference. Formula. The formula used to calculate circle circumference is: C = π · ø. Symbols. C = Circle circumference; π = Pi = 3.14159… ø = Circle diameter; Diameter of Circle. Enter the diameter ...How To Find Circumference From Diameter Guide. You can also select units of measure for both input data and results.This circumference to diameter calculator is used to find the diameter of a circle given its circumference.That is to say, you can find the circumference of a circle just by multiplying the diameter by pi. in regards to synonymCircumference and area vs circle diameter Google use cookies for serving our ads and handling visitor statistics. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.Find the exact circumference of eSolutions M. anual - Powered by Cognero. 10. Name the center of the circle. SOLUTION: R. SOLUTION: The circumference C of a circle with diameter d is given by Here, C = 124 ft. Use the formula to find the diameter.3. If you know the area of the circle, divide the result by π and find its square root to get the radius; then multiply by 2 to get the diameter. This goes back to manipulating the formula for finding the area of a circle, A = πr 2, to get the diameter. You can transform this into r = √ (A/π) cm. Example.Find radius, circumference, area of circle, diameter of a cirlce, and learn the difference between radius & diameter (radius vs diameter) with the formula for Circumference = π × diameter = 2 × π × radius. Use the apps, videos and worksheet available on this page to learn the formulas to find the...circumference formula = C = PI*Diameter. to find Diameter, divide Circumference by PI. Please mark Brainliest.Apr 10, 2022 · Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm. If the circumference of a circle is known then we can easily find the value of the diameter by substituting the values in the formula: Diameter = C ÷ π; where 'C' is the circumference and the value of π is 22/7 or 3.14 approximately.Generally, the diameter is used to calculate the circumference, therefore, it is also possible to calculate the length of the diameter if we have the circumference The formula for the circumference is: where, C is the length of the circumference and π is a mathematical constant that has an approximate value of 3.1416. Circumference to Diameter Calculator. This circumference to diameter calculator is used to find the diameter of a circle given its circumference. Just enter the value of the circumference. Then tap or click the Calculate button. Get the result. You can also select units of measure for both input data and results. The diameter of a circle will be shown in the selected units. The radius, the diameter, and the circumference are the three defining aspects of every circle. Given the radius or diameter and pi you can calculate the circumference. The diameter is the distance from one side of the circle to the other at its widest points. The diameter will always pass through the center of the circle.How To Find Circumference From Diameter Guide. You can also select units of measure for both input data and results.This circumference to diameter calculator is used to find the diameter of a circle given its circumference.That is to say, you can find the circumference of a circle just by multiplying the diameter by pi. Circles on ACT math test your knowledge of radii, circumferences, areas, and more. Learn important circle formulas and strategies and practice on real math problems here. This will be your complete guide to ACT circles, including areas, circumferences, degrees, arcs, and points on a circle.Circumference to Diameter Formula To Find & Convert. How. To calculate the diameter of a circle with circumference 1 cm, use the formla of C = πd, or d = C/π, where C is the circumference and d is the diameter.Apr 10, 2022 · Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm. Finding the Diameter from the Circumference The circumference can be divided by {eq}\pi {/eq} to find the diameter. Remember that the formula for the circumference of a circle is {eq}C = d \pi = 2 ...To find the diameter of the circle from its circumference, we do a little re-arranging of variables in the formula: {eq}C=d \pi {/eq} Divide both sides by {eq}\pi {/eq}Diameter from Circumference The diameter of a circle can be found from the circumference using the formula below In this mini-curriculum, you will learn about how to find the area of a circle from its diameter.circumference formula = C = PI*Diameter. to find Diameter, divide Circumference by PI. Please mark Brainliest.I was 10 yrs. old in Mexico and learned that Circumference = Diameter times pi(3.14). So, if you have a circle with a diameter (from edge to edge) of 5 in. you Now to find the area of a circle, you square (multiply the # by itself) X the radius (from center to edge). So, as in the 1st. example the diameter...1 crore to cadFind the exact circumference of eSolutions M. anual - Powered by Cognero. 10. Name the center of the circle. SOLUTION: R. SOLUTION: The circumference C of a circle with diameter d is given by Here, C = 124 ft. Use the formula to find the diameter.If you want to know how to find the diameter of a circle, particularly how to measure the diameter of a circle, it is handy to have a few formulas in your ba...Find the diameter, radius, circumference and area of the circle shown below. use 3.14 as an approximation for π. How to Find the Length of Latus Rectum of a Parabola.The diameter of a circle is the length of the line through the center and touching two points on its For example: enter the diameter and press 'Calculate'. The area, radius and circumference will Repeat the above and note how the radius is always half the diameter no matter what the size of the circle.Circumference of a circle (which is the perimeter of a circle) is the length of the circular line that marks the limits of a circle. Formula for the circumeference of a circle = 2 x π x r = π x d where r is the radius and d, the diameter. Thus, ratio of circumference to diameter = π. You now have the circumference of your finger. Find your measurement on our ring size conversion chart to get your approximate ring size. If you don't know what letter you need, you can find out below using the circumference of your finger or the diameter of an existing ring that fits.Practice Problem: Find the area and circumference of a circle with a diameter of 4 inches. Solution: One of the first rules of solving these types of problems involving circles is to carefully note whether we are dealing with the radius or the diameter. In this problem, the circle is described using the diameter, which is 4 inches. know how to find the perimeter (circumference) of a circle; solve word problems involving perimeter of circles; Want to test yourself to see how well you have understood this skill?. find the diameter of the circle (the distance from one side to the other in a straight line through the middle).How to Calculate Diameter From Circumference Sciencing. This online diameter to circumference converter helps you to find the perimeter value from the given diameter at desired units.If you want to know how to find the diameter of a circle, particularly how to measure the diameter of a circle, it is handy to have a few formulas in your ba...Mar 24, 2022 · We know that the circumference of a circle = 2 π r. = 2 × 3.14 × 50 cm. = 314 cm. To find the number of revolutions of the wheel, divide the distance covered by the circumference of the wheel. To convert 157 metres to cm multiply by 100. Number of revolutions = 15700 314 = 50 revolutions. How to find the area of a circle? S = π × r² = (π × D²) ⁄ 4 = (c × D) ⁄ 4, where r, D and c are the radius, diameter and circumference of a circle respectively.This tool will calculate the circumference of a circle from the diameter, and will convert different measurement units for diameter and circumference. Formula. The formula used to calculate circle circumference is: C = π · ø. Symbols. C = Circle circumference; π = Pi = 3.14159… ø = Circle diameter; Diameter of Circle. Enter the diameter ...Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm.Apr 10, 2022 · Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm. costa replacement partsPractice naming circles and calculating circumference, radius, diameter, and area of a circle. When your students sing the pi song, they'll never forget how to calculate the circumference and area of a circle. Find the diameter and radius of each circle. Also, figure out which circles are the largest...Circumference to Diameter Calculator. This circumference to diameter calculator is used to find the diameter of a circle given its circumference. Just enter the value of the circumference. Then tap or click the Calculate button. Get the result. You can also select units of measure for both input data and results.Find the radius of a circle with circumference of 31.4 cm. In this problem we need to work backwards to find the radius. We start by plugging in the information we know: If we divide each side of the equation by π, or 3.14, we will get the diameter: Now, if we cut that in half we can find the radius.We have another article which describes how to measure rims for spokes. What size tire do you need to buy for your bicycle? There are so many different tire sizes and different systems for marking tire sizes that have been used over the years that this You derive the diameter from the circumference.how to find radius from circumference. In addition to the radius, there is also the diameter. The diameter is twice as large as the radius. The formula looks like this: d = 2 * r. For example, if the radius of a circle is 2 meters, then the diameter is 4 meters. In addition, the so-called circle number π (pronounced: pi) is required.In this video you will learn how to work out the diameter of a circle from its circumfernce. You can do this in one step by dividing the circumfernce by Pi. ...know how to find the perimeter (circumference) of a circle; solve word problems involving perimeter of circles; Want to test yourself to see how well you have understood this skill?. find the diameter of the circle (the distance from one side to the other in a straight line through the middle).How big is Earth? Find out here. Radius, diameter and circumference. Density, mass and volume. Highest and lowest points. Earth, the third planet from the sun, is the fifth-largest planet in the solar system; only the gas giants Jupiter, Saturn, Uranus and Neptune are bigger.How to Calculate Diameter From Circumference Sciencing. Economy. Details: The distance around the edge of the circle is called the circumference. › Get more: Use circumference to find diameterView Economy. Circumference to Diameter Formula To Find & Convert.dog for saleHow To Find Circumference From Diameter Guide. You can also select units of measure for both input data and results.This circumference to diameter calculator is used to find the diameter of a circle given its circumference.That is to say, you can find the circumference of a circle just by multiplying the diameter by pi. know how to find the perimeter (circumference) of a circle; solve word problems involving perimeter of circles; Want to test yourself to see how well you have understood this skill?. find the diameter of the circle (the distance from one side to the other in a straight line through the middle).Find the diameter, radius, circumference and area of the circle shown below. use 3.14 as an approximation for π. How to Find the Length of Latus Rectum of a Parabola.How To Calculate Diameter From Circumference | Sciencing. The system has given 14 helpful results for the search "how to find the circumference from diameter". These are the recommended solutions for your problem, selecting from sources of help.Diameter can be found by multiplying the radius by two, or by dividing the circumference by PI (3.14159). What is the equation to find the diameter of a circle? The diameter is made up of two segments that are each a radius. Circumference of the circle = 2πr cm. Given, Circumference of a cicle = 44cm. Therefore, 2πr = 44 (from above) r = 7cm. Diameter of the circle = 2r = (2 x 7)cm = 14cm. Hence, the Diameter of the circle is 14 cm. Question 2. Find the diameter of the circle whose circumference is 132 cm? Explanation. Let, the radius of the given circle be r cm ...Apr 10, 2022 · Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm. Diameter can be found by multiplying the radius by two, or by dividing the circumference by PI (3.14159). What is the equation to find the diameter of a circle? The diameter is made up of two segments that are each a radius. The diameter is the length of the line through the center that touches two points on the edge of the circle known as the circumference.. Formula to calculate diameter (d) from circumference (C).Revolutions specifies, how often the wheel turns around at the covered distance. Radius of a wheel is the span between center and edge, diameter ist twice the radius, the span from edge to opposite edge. Circumference is the distance a wheel covers at one revolution.Revolutions specifies, how often the wheel turns around at the covered distance. Radius of a wheel is the span between center and edge, diameter ist twice the radius, the span from edge to opposite edge. Circumference is the distance a wheel covers at one revolution.mary kay perfumesCircumference to Diameter Formula To Find & Convert. How. To calculate the diameter of a circle with circumference 1 cm, use the formla of C = πd, or d = C/π, where C is the circumference and d is the diameter.know how to find the perimeter (circumference) of a circle; solve word problems involving perimeter of circles; Want to test yourself to see how well you have understood this skill?. find the diameter of the circle (the distance from one side to the other in a straight line through the middle).How to Calculate Diameter From Circumference Sciencing. This online diameter to circumference converter helps you to find the perimeter value from the given diameter at desired units.The diameter is the length of the line through the center that touches two points on the edge of the circle known as the circumference.. Formula to calculate diameter (d) from circumference (C).The circumference of the circle having a diameter of 8 feet is calculated using the equation: C= 2⋅π⋅r C = 2 ⋅ π ⋅ r. where. C C is the circumference, r = 8 ft 2 = 4 f t r = 8 f t 2 = 4 ... Circumference of the circle = 2πr cm. Given, Circumference of a cicle = 44cm. Therefore, 2πr = 44 (from above) r = 7cm. Diameter of the circle = 2r = (2 x 7)cm = 14cm. Hence, the Diameter of the circle is 14 cm. Question 2. Find the diameter of the circle whose circumference is 132 cm? Explanation. Let, the radius of the given circle be r cm ...Find the diameter of a circle with a circumference of 32 cm. Solution 1: To solve this problem, you will require the formula to find the circumference of a circle using the diameter i.e. C = πd. Now, fill in the given details. 32 = (3.14)d. Next, divide both sides by 3.14. Thus, 3.14 will neutralize on the right side of the equation, leaving d. Geometry Tutorial explains how to find the circumference of a circle with easy to follow problems and solutions. By following along with the examples given and taking the online Math Made Easy! geometry quiz for circumference of a circle, you will be able to complete your geometry homework on...Head circumference (HC) is one of the basic biometric parameters used to assess fetal size. HC together with biparietal diameter (BPD), abdominal circumference (AC), and femur length (FL) are computed to produce an estimate of fetal weight.Apr 10, 2022 · Calculate the Diameter of a Circle Starting from the Radius, Circumference or Area. If you know the radius, you simply need to double it to get the diameter. The radius is the distance from the center to the edge. If the radius is 4cm, the diameter is 4cm x 2 = 8cm. To find the diameter of the circle from its circumference, we do a little re-arranging of variables in the formula: {eq}C=d \pi {/eq} Divide both sides by {eq}\pi {/eq}fuel cards for truckers -fc