Go Back  Quiltingboard Forums >
  • General Chit-Chat (non-quilting talk)
  • How is/was "pi" calculated? >
  • How is/was "pi" calculated?

  • How is/was "pi" calculated?

    Thread Tools
     
    Old 03-09-2011, 11:21 AM
      #1  
    Power Poster
    Thread Starter
     
    Join Date: May 2008
    Location: MN
    Posts: 24,581
    Default

    I was taught that "pi" is the ratio of the radius and/or diameter of a circle to its circumference.

    What circle's circumference and diameter were measured to be able to get a number that has hundreds of numbers after the decimal point?

    For many practical purposes, 22/7 (3-1/7) or 3.1416 seems to be a fairly close approximation.
    bearisgray is offline  
    Old 03-09-2011, 11:23 AM
      #2  
    Guest
     
    Join Date: Jan 2011
    Location: Cypress, Texas
    Posts: 4,728
    Default

    lol...I remember 3.14 from school.
    emerald46 is offline  
    Old 03-09-2011, 11:25 AM
      #3  
    Super Member
     
    Join Date: Apr 2007
    Posts: 1,933
    Default

    The decimal number is just a close approximation of the irrational fraction 22/7.
    isnthatodd is offline  
    Old 03-09-2011, 11:28 AM
      #4  
    Guest
     
    Join Date: Jan 2011
    Location: Cypress, Texas
    Posts: 4,728
    Default

    Pi is the ratio of the circumference of a circle to its diameter. Pi = C/D. Pi is always the same number. Pi = 3.14159 rounded..how about this..Sorry I love math!
    emerald46 is offline  
    Old 03-09-2011, 11:30 AM
      #5  
    Super Member
     
    Join Date: Dec 2010
    Posts: 1,232
    Default

    Originally Posted by bearisgray
    I was taught that "pi" is the ratio of the radius and/or diameter of a circle to its circumference.

    What circle's circumference and diameter were measured to be able to get a number that has hundreds of numbers after the decimal point?

    For many practical purposes, 22/7 (3-1/7) or 3.1416 seems to be a fairly close approximation.
    I do believe that the ratio of the circumference to the diameter of ANY circle will be 'pi'. It's also the ratio of the area of the circle to the square of its area.

    Are you celebrating National PI day next Monday (3/14)?
    quilt1950 is offline  
    Old 03-09-2011, 11:37 AM
      #6  
    Senior Member
     
    Vickymomof6's Avatar
     
    Join Date: Dec 2008
    Location: New York
    Posts: 817
    Default

    In my circles pi is spelled pie and it is usually sliced in about 6 to 8 pieces.


    Sorry I couldn't resist :-P
    Vickymomof6 is offline  
    Old 03-09-2011, 11:37 AM
      #7  
    Super Member
     
    Join Date: Mar 2010
    Location: Anchorage, AK
    Posts: 1,396
    Default

    Emerald and quilt1950 are correct...doesn't make any difference on the circumference...the ration of circum. to diameter is ALWAYS pi.
    ktbb is offline  
    Old 03-09-2011, 11:50 AM
      #8  
    Super Member
     
    jdiane318's Avatar
     
    Join Date: Aug 2010
    Location: springfield, MO
    Posts: 2,033
    Default

    Whatever it is, isn't it obvious that only a man could come up with something neverending and repetitious? A woman wouldn't.
    jdiane318 is offline  
    Old 03-09-2011, 11:51 AM
      #9  
    Power Poster
     
    Join Date: May 2009
    Location: NY
    Posts: 10,590
    Default

    Originally Posted by Vickymomof6
    In my circles pi is spelled pie and it is usually sliced in about 6 to 8 pieces.


    Sorry I couldn't resist :-P
    ROFL!! 6 to 8?!!? in my circles we are lucky to get 4! :XD:
    feline fanatic is offline  
    Old 03-09-2011, 12:19 PM
      #10  
    Super Member
     
    Join Date: Aug 2010
    Location: Roswell, NM
    Posts: 1,727
    Default

    Originally Posted by ktbb
    Emerald and quilt1950 are correct...doesn't make any difference on the circumference...the ration of circum. to diameter is ALWAYS pi.
    Ditto!
    greensleeves is offline  
    Related Topics
    Thread
    Thread Starter
    Forum
    Replies
    Last Post
    bearisgray
    Main
    8
    10-09-2011 05:56 AM

    Posting Rules
    You may not post new threads
    You may not post replies
    You may not post attachments
    You may not edit your posts

    BB code is On
    Smilies are On
    [IMG] code is On
    HTML code is On
    Trackbacks are Off
    Pingbacks are Off
    Refbacks are Off



    FREE Quilting Newsletter