How did Pi come about?
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Since ancient history regarding the concept.\n\nHistory of the notation:\n\nThe symbol "π" for Archimedes' constant was first introduced in 1706 by William Jones when he published A New Introduction to Mathematics, although the same symbol had been used earlier to indicate the circumference of a circle. The notation became standard after it was adopted by Leonhard Euler. In either case, 'π' is the first letter of περιφέρεια (periphereia, the Greek word for periphery) or περίμετρον (perimetron), meaning 'measure around' in Greek.
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A crude approximation to pi. The Babylonians had a better one 355/113 which is 3.141592
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history of PI~~\nthe symbol "π" for Archimedes' constant was first introduced in 1706 by William Jones when he published A New Introduction to Mathematics, although the same symbol had been used earlier to indicate the circumference of a circle. The notation became standard after it was adopted by Leonhard Euler. In either case, 'π' is the first letter of περιμετρος (perimetros), meaning 'measure around' in Greek
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Pi is the ratio of the circumferance of a circle to its diameter.  The following equation is for the area of a circle:    A = pi*r^2\n\nThe Math Forum website has a very complete and east-to-understand explanation.
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The common symbol often used for pi, is the lowercase Greek letter P.  Euler popularized William Jones use of the symbol, which Jones first put the symbol to the number in 1706. Other mathmaticians before that had applied the symbol to related ratios.
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The value of pi was not very well calculated during that time period. In fact, Archimedes (about 200 BC) was able to say that it is between 3 10/71 and 3 1/7. This is only a 2 decimal place accuracy. However, he did give a method involving polygons to obtain better approximations.\n\nThe Egyptians had a rather unusual system for fractions which was rather cumbersome to work with. They did multiplication and division by doubling, halving, and addition.\n\nThe intellectual Greeks and Romans tended to use the Babylonian system which was a base 60 system. The methods were fairly similar to our system. For things like square roots, they did successive approximations. The specific approximations used depend on the time period.
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The value of π has been known in some form since antiquity. As early as the 19th century BC, Babylonian mathematicians were using π=25/8, which is within 0.5% of the exact value.\n\nThe Egyptian scribe Ahmes wrote the oldest known text to give an approximate value for π, citing a Middle Kingdom papyrus, corresponding to a value of 256 divided by 81 or 3.160.\n\nIt is sometimes claimed that the Bible states that π=3, based on a passage in 1 Kings 7:23 giving measurements for a round basin as having a 10 cubit diameter and a 30 cubit circumference. Rabbi Nehemiah explained this by the diameter being from outside to outside while the circumference was the inner brim; but it may suffice that the measurements are given in round numbers. Also, the basin may not have been exactly circular.\n\nThe Chinese mathematician Liu Hui computed π to 3.141014 (good to three decimal places) in AD 263 and suggested that 3.14 was a good approximation.\n\nThe Indian mathematician and astronomer Aryabhata in the 5th century gave the approximation π = 62832/20000 = 3.1416, correct when rounded off to four decimal places.\n\nThe Chinese mathematician and astronomer Zu Chongzhi computed π to be between 3.1415926 and 3.1415927 and gave two approximations of π, 355/113 and 22/7, in the 5th century.\n\nThe Indian mathematician and astronomer Madhava of Sangamagrama in the 14th century computed the value of π after tranforming the power series expansion of π/4 into the form\n\nπ = √12(1 - 1/(33) + 1/(532) - 1/(733) + ... \nand using the first 21 terms of this series to compute a rational approximation of π correct to 11 decimal places as 3.14159265359. By adding a remainder term to the original power series of π/4, he was able to compute π to an accuracy of 13 decimal places.\n\nThe Persian Muslim mathematician and astronomer Ghyath ad-din Jamshid Kashani (1350-1439) correctly computed π to 9 digits in the base of 60, which is equivalent to 16 decimal digits as:\n\n2 π = 6.2831853071795865 \nThe German mathematician Ludolph van Ceulen in 1615 computed the first 32 decimal places of π. He was so proud of this accomplishment that he had them inscribed on his tombstone.\n\nIn 1789, the Slovene mathematician Jurij Vega improved John Machin's formula from 1706 and calculated the first 140 decimal places for π of which the first 126 were correct [1] and held the world record for 52 years until 1841, when William Rutherford calculated 208 decimal places of which the first 152 were correct.\n\nThe English amateur mathematician William Shanks, a man of independent means, spent over 20 years calculating π to 707 decimal places (accomplished in 1873). In 1944, D. F. Ferguson found (with the aid of a mechanical desk calculator) that Shanks had made a mistake in the 528th decimal place, and that all succeeding digits were fallacious.
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cute question. you have imagination. I think he was pi$$ed
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PI(π)= 3.14159 26535 89793 23846 26433 83279 50288 41971 69399 37510...\nIt is a Greek letter, and an irrational number. Some formulas it is used in include the formulas for area/perimeter of a circle, surface area of a sphere, and volume of a cylinder. Pi may be defined either as the ratio of a circle's circumference to its diameter, or as the ratio of a circle's area to the area of a square whose side is the radius.
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PI= π = 22/7 = 3.1428571428571428571428571428571\n\nIn Euclidean plane geometry, π may be defined either as the ratio of a circle's circumference to its diameter, or as the ratio of a circle's area to the area of a square whose side is the radius. Advanced textbooks define π analytically using trigonometric functions, for example as the smallest positive x for which sin(x) = 0, or as twice the smallest positive x for which cos(x) = 0.\n\nAll these definitions are equivalent, they amount to the following numerical value of π, truncated to 50 decimal places:\n\n3.14159 26535 89793 23846 26433 83279 50288 41971 69399 37510
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Pi is the ratio of circumfarence of circle to the diameter. It is irrational and approximated by 22/7\n\nThis can be defined as 4(tan ^-1 1)
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Impossible to answer.  Pi is an irrational number meaning that the numbers after the decimal will continue until infinity.  While supercomputers can give the number to "upteen" decimal places, we can never know the last decimal place.
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From Wiki:"The use of the Greek letter π for this constant is derived from Greek words like περιφέρεια (for periphery) and περίμετρον (for perimeter) starting with this letter.\nThe name of the Greek letter π is pi, and this spelling is used in typographical contexts where the Greek letter is not available or where its usage could be problematic. When referring to this constant, the symbol π is always pronounced like "pie" in English, the conventional English pronunciation of the letter."\n\nFrom Online Etymology Dictionary:\nPi: "1841, used in L. 1748 by Swiss mathematician Leonhart Euler (1707-83), from Gk. letter pi (from Heb., lit. "little mouth") as an abbreviation of Gk. periphereia "periphery." "\n\nMy initial guess was that it was derived from Latin, since many of our words have Latin origins.  But, apparently it is Greek in origin and is used because the Greek symbol Pi means perimeter thus corresponding to circles.
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Pi is the ratio of a circle's diameter to its circumference as well as the ratio of the circle's area to a square with the same sidelength as its radius. This made Pi useful to many ancient societies, as the circle is the shape that encloses the largest area with a given circumference, so we don't really know who formulated the importance of Pi first. \nDue to the n-dimensional circle (n-sphere) being a model for periodic phenomena, a natural way of measuring angles (the radian and steradian are inspired by the 1- and 2-sphere respectively) and homeomorphisms of the n-dimensional ball being important in differential geometry and manifold theory (integrals of forms over spheres are common in physics), Pi shows up almost everywhere in modern mathematics and physics.
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ramanujan worked in many fields but he did devise an infinite series that very accurately determines pi which can be found here http://en.wikipedia.org/wiki/Ramanujan#Theorems_and_discoveries
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Pi is the result of dividing the diameter of a circle by its circunference.
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Pi is never mentioned in the Bible; it is implied!   We (and let me repeat, we) deduce that pi is the 30 cubits around by 10 cubits brim to brim simplifies to just 3.    \n\nThe translations of the Bible over the span of mankind have changed the wordings and even the meanings of some verses.\nSince the original author(s) of Kings was inspired by God they would have spent their minds on faith and poetic emotion rather than intense technical information such as describing decimals.  The information for someone building or doing basic construction can and easily get by with just an approximate value of 3