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Pi Misconception 
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#1
Mar1514, 04:38 AM

P: 3

Happy Pi day folks !
Heres a general misconception im having. It might turn out to be a pretty easy question so please do help me. If i pull out my compass to a radius of 7 cm and draw a circle on a paper. Then i'll take a piece of thread and cut it such that it matches exactly with the circle on paper and take the length of that particular thread and divide by 14cm, should i get the value of pi ? If its so, why isnt pi an irrational number. After all im dividing the circumfrence i've got by 14 cm. So it should a rational number. For example, if the circumfrence is 50.123456 cm ( i've not measured yet just an example) And i divide it by 14cm I shall get 50123456/14000000 as value of pi, which is supposedly rational ? Is it an contradiction ? 


#2
Mar1514, 04:57 AM

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(this is a message from the future … it's actually Piplusone day here … are you in Alaska?) No matter to how many decimal places you try to measure it, you'll always find a little left over! 


#3
Mar1514, 05:21 AM

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#4
Mar1514, 08:15 AM

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Pi Misconception



#5
Mar1514, 08:16 AM

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 That the circle's radius is exactly 7 cm.  That this circle drawn with a compass truly is a circle. 


#6
Mar1514, 08:37 AM

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 The thread perfectly tracing the circle.  The thread perfectly maintaining that same length after being stretched out straight.  The ruler being perfect. Even the thread's physical properties are limiting the perfectness of this imperfect exercise. 


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