Thread: pi
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Old 11-16-2012, 06:47 PM
  #3  
Blue Cat
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Join Date: Sep 2012
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The calculator value is much more accurate. 22/7 is an approximation for use with fractions. As you say, however, either one is close enough to get you scant quarter seamline.

laura


Originally Posted by bearisgray View Post
My calculator gives the value of pi as: 3.14159365359

My calculator give the value of 22/7 (3-1/7) as: 3.14285714286


22/7 has a repeating decimal as the value and, as far as I know, pi goes on forever.

Anyway -

for most purposes in my life - as in drafting a pattern - 22/7 - works well enough for most calculations.
0.00126 - a bit more than one-thousandth of an inch variation will probably work well enough with 'a scant quarter inch' seam
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