This method won't work with ellipses, ovals or anything but a real circle. A circle is defined as all the points on a plane that are an equal distance from a single center point. The lids of jars are good household objects to use for this exercise.You should be able to calculate pi roughly because in order to get exact results of pi, you will need to have a very thin lead(or whatever you are using). Even the sharpest pencil graphite could be huge to have exact results. The circumference is the length that goes around the entire edge of the circle. Since the circumference is round, it can be difficult to measure (that's why pi is so important). Lay a string over the circle as closely as you can. Mark the string off where it circles back around, and then measure the string length with a ruler. The diameter runs from one side of the circle to the other through the circle's center point. The circumference of a circle is found with the formula C= π*d = 2*π*r. Thus pi equals a circle's circumference divided by its diameter. Plug your numbers into a calculator: the result should be roughly 3.14. This will give you more accurate results. Your measurements might not be perfect on any given circle, but over time they should average out to a pretty accurate calculation of pi.
सुनिश्चित करिए कि आप एक सम्पूर्ण सर्किल का उपयोग कर रहे हैं: सर्किल की परिधि को आप उतना सही नापें जितना आप कर सकते हैं: सर्किल के डायमीटर को नापें: फ़ोर्मुले का प्रयोग करें: इस प्रक्रिया को अनेक भिन्न सर्किलों पर दोहराएँ, और फिर परिणामों का औसत निकालें: