Taylor aarambh pi
- 1. The Mysteries of Pi by Taylor and Aarambh
- 2. Pi’s Early History Different cultures had different values. The Ancient Babylonians used 3 1/8 for their value of pi by taking 3 times the square of a circles radius which was 3 1/8. The Egyptians used (16/9)2 The Chinese said pi was 3. The Hebrews said pi was 3 also, based on what they learned in the bible.
- 3. More of Pi’s History In Egypt in the 400’s B.C, a mathematician named Euclid proved that the ratio of the circumference to the diameter of a circle is always the same. Archimedes studied in Alexandria. He discovered the value of pi to be about 22/7 We still use this approximation today. . Archimedes’s method for approximating pi: The area of the circle is in the areas of the circumscribed and the inscribed hexagons.
- 4. Calculating Pi To calculate an approximate value of pi, measure the diameter and the circumference of a circle (using a piece of string perhaps). Divide the circumference of the circle by the diameter. Keep in mind: This is an approximation.
- 5. Class Activity: #1 ! ! ! "#$%! Calculate the circumference – C – of the circle above using one of the following equations: C=2πr or C=πd r=radius d=diameter
- 6. #2 ! ! ! "#$%! Calculate the area – A – of the circle above using one of the following equations: A=πr2 or A=πd2/ 4 r=radius d=diameter
- 7. #3 ! ! ! "#$%&! ! ! "#$%&! Calculate the volume – V – of the cylinder above using one of the following equations: V=πr2h or V=πd2/ 4h r=radius d=diameter h=height
- 8. Answers: #1 C = 2πr C = 2 x 3.14 x 3 C = 18.84 inches OR C = πd C = 3.14 x 6 C = 18.84 inches
- 9. #2 A = πr2 A = 3.14 x r x r A = 3.14 x 3 x 3 A = 28.26 inches OR A = πd2/4 A = 3.14 x d x d /4 A = 3.14 x 6 x 6 / 4 A = 28.26 sq. inches
- 10. #3 V = πr 2 x h V= 3.14 x 10 x 10 x 30 V = 9420 cubic inches
- 11. Bibliography The Amazing History of Pi. 23 Apr. 2010. <http://ualr.edu/ lasmoller/pi.html>. The Everlasting Pi. 29 Apr. 2010. <http://abishek.webs.com/ usesofpi.htm>.