× Didn't find what you were looking for? Ask a question
Top Posters
Since Sunday
a
5
k
5
c
5
B
5
l
5
C
4
s
4
a
4
t
4
i
4
r
4
r
4
Home Q & A Board Science-Related Homework Help Mathematics
New Topic  
riri87 riri87
wrote...
Posts: 4
Rep: 0 0
10 years ago
They say that a rational number is one that can be expressed as a ratio between two integers in a form a/b where b is not equal zero.

Since Pi can be expressed as 22/7, wouldn't we need a different definition of rationality? What is the difference?
Read 275 times
6 Replies

Related Topics

Replies
wrote...
#1
10 years ago
Actually 22/7 is only an approximation of pi.  Convert it to a decimal and you get 3.142857... while pi is actually 3.14159...
wrote...
#2
10 years ago
Pi is roughly 22/7, the true measurement of Pi is Circumference / Diameter

Pi = 3.14159265
22/7 = 3.14285714
wrote...
#3
10 years ago
22/7 is only an approximation that is close to the real value
The real value to 50 places is
3.141592653589793238462643383 27950288419716939937510...

22/7 = 3.142857142857142857...

Pi is an irrational number that can not be expressed as a single fraction, but as an inifinite series of ever changing fractions.  There is no known repeat pattern and it has been caluclated to over a trillion places.
wrote...
#4
10 years ago
Pi = 3.141592653589793238462643383 2795 it wont stop right there it will keep going and going

22/7  is an approximation for Pi

but 22/7 = 3.142857142857142857142857142 8571 which is right only for two decimal places

You can't write pi in any p /q form. Thar's why it's a irrational number.
wrote...
#5
10 years ago
Pi is NOT a rational number, 22/7 is an approximation. However, Pi is a transcendental number. Transcendental numbers are irrational numbers that are not roots of polynomial equations with rational coefficients.
Another transcendental number is e, the base of natural logarithms.

Aside:
Quote: "Why do they define . . . ."
Who are 'they'? Obviously not mathematicians, for a start!
.
wrote...
#6
10 years ago
if you ask google calculator (which i find really easy)

-  -  -  - pi = 3.14159265   Leftwards Arrow there are more digits, but this is enough for our purposes.
355/113 = 3.14159292  Leftwards Arrow much better estimate than 22/7
-  - 22 /7 = 3.14285714

355/113 is a far better fraction, but still not exact.
New Topic      
Quick Reply
Explore
Post your homework questions and get free online help from our incredible volunteers
  1034 People Browsing
Start New Topic Take the Tour CoursesNew Study Tools Topics Trending Browse by Textbook
Live Chat
Related Images
  
 175
  
 38
  
 270