", "This article will help me pass the math exams for getting a score in school. You convert inches to feet the same way to find the area of a circle as you do to find anything else. You can find the area of a circle using the radius, the diameter, or the circumference. If you want to report a numerical value, you can multiply 120 x 3.14 to get a value of 376.8 cm. C = pi * d calculates the circumference (distance around the outside of the circle). Make sure you know if you are measuring the small angle between the two radii or the greater angle outside them. The formula is simple and only needs the radius of the circle to find its area. Include your email address to get a message when this question is answered. She has taught math at the elementary, middle, high school, and college levels. Also, know how to calculate the segment of a circle using examples with its types and theorems here. To find the area using the diameter, or the distance from one side of the circle to the other, first divide the diameter in half to find the radius. The radius will generally be provided to you. ", "I only had a slim clue on how to calculate the area of a circle, and this helped me fully understand. = 5 m Summary: Given the radius or diameter of a circle, we can find its area. Square the radius and multiply by pi to find the area. It can be determined easily using a formula, A = πr2, (Pi r-squared) where r is the radius of the circle. It supports different units such as meters, feet, and inches. The formula for working out the area of a circle is: \ (A = \pi r^2\), where \ (r\) is the radius of the circle. How do I calculate the circumference of a circle? Half the diameter is the radius. This free area calculator determines the area of a number of common shapes using both metric units and US customary units of length, including rectangle, triangle, trapezoid, circle, sector, ellipse, and parallelogram. The formula for the area of a circle is A = pi * r * r where r is the radius (diameter / 2). Ten squared is 100, and 100 times π is 314.16. Find the area of a circle given its radius, diameter, or circumference. wikiHow helps with its clear instructions and explanations, even on depressing afternoons where nothing math-related seems to be going right. ", "Math has never been my strong point. Then, plug the radius into the formula for finding area, area = πr^2. Whenever I do not know something, I always come to this website! You can find the PI value up to 1,00,000 Decimal Digits. The area of a circle is number of square units inside the circle. 1 foot = 12 inches, or 1 inch = 1/12 foot. (If you're asking how to convert from square inches to square feet, divide the number of square inches by 144 to get square feet.). Grace Imson is a math teacher with over 40 years of teaching experience. By using our site, you agree to our. The area of a circle is calculated by finding the square of the radius and multiplying this result by . or, when you know the Circumference: A = C2 / 4π. It doesn't matter whether you want to find the I found this and finished really quickly! Math Instructor, City College of San Francisco. Thank you so much! Find the area of major and minor segments (Take π = 3.14) Sol. If you want to find the area of a sector from a circle, keep reading the article! The holes are circular (in cross section) because they are drilled out using an auger. This article was co-authored by Grace Imson, MA. In this article, we will illustrate c program to calculate area of circle.The formula for the area of the circle is : Area_circle = Π * r * r where, mathematical value of Π is 3.14159. Visual on the figure below: Find Area of Circle To calculate area of any circle in C++ programming, you have to ask from user to enter the radius of circle, place the radius in a variable say rad and then initialize 3.14*rad*rad in a variable that holds the value of area of circle, as shown here in the following program. (even though pies are usually round). How do I find the total area of five circles joined together? Draw a perpendicular from the center of the circle to the third side of the triangle and use the sine and cosine of 72/2 = 36 degrees. Now let's move on to the program. You need to know the formula for finding the area of a circle, A=πr2{\displaystyle A=\pi r^{2}}. If the pipe was made after WWII, try a comparison. It has always been a tricky situation for me, "Thanks. The Formula for Area of Circle Area of a Circle = πr2 or PI * Radius * Radius. you have five copies of an isosceles triangle and you know all the side lengths, so you should be able to find the area of the triangle and therefore, the whole pentagon. ", "Thx for this article. How to Find the Area of a Circle Using Its Circumference. ", "I think this really helped me. wikiHow is where trusted research and expert knowledge come together. Therefore, the area of the circle is 314.16 inches squared. Last Updated: December 27, 2020 We can plug in our known area into the formula and work from the inside out. Let’s calculate the are Somewhere in your problem, you must be provided with the radius of each circle, or some way of determining the radius, diameter or circumference of each circle. So Max should order 0.126 cubic meters of concrete to fill each hole. For example, if the diameter is 20 inches, you would divide that in half and get 10 inches. The calculations are done "live": To help you remember think "Pie Are Squared" Can you see the next step? A = π2 2 A = 4π {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/6\/65\/Calculate-the-Area-of-a-Circle-Step-1-Version-6.jpg\/v4-460px-Calculate-the-Area-of-a-Circle-Step-1-Version-6.jpg","bigUrl":"\/images\/thumb\/6\/65\/Calculate-the-Area-of-a-Circle-Step-1-Version-6.jpg\/aid53808-v4-728px-Calculate-the-Area-of-a-Circle-Step-1-Version-6.jpg","smallWidth":460,"smallHeight":345,"bigWidth":728,"bigHeight":546,"licensing":"