MHB What are some interesting approximations of pi?

Click For Summary
The discussion highlights various interesting approximations of pi, including the well-known $\frac{22}{7}$ and $\frac{355}{113}$, which accurately represents pi to six decimal places. An intriguing approximation mentioned is the sum of two surds, $\sqrt{2} + \sqrt{3}$. A mnemonic for remembering pi is noted: "May I have a large container of coffee," where the letter count corresponds to the digits of pi. Additionally, the thread references a collection of unique approximations and celebrates a specific "Wagon Wheel Approximation of Pi" featured on Pi Day. The conversation invites further contributions on interesting observations related to pi.
kaliprasad
Gold Member
MHB
Messages
1,333
Reaction score
0
we know a couple of approximate values of $\pi$ mostly $\frac{22}{7}$ and $\frac{355}{133}$ but one I found (from the net )interesting was sum of 2 surds $\sqrt{2} + \sqrt{3}$.if anyone is aware of other of interesting observation kindly let me know.
 
Mathematics news on Phys.org
Not an approximation but a mnemonic: "May I have a large container of coffee". The number of letters in each word: 3.1415926.
 
There is a collection of weird and wonderful approximations for pi here. My favourite is the approximation $\frac{355}{113}$, which gives the first six decimal digits of $\pi$ correctly, even though the numerator and denominator of the fraction have only three digits. The reason for that is that the following term in the continued fraction expansion of $\pi$ is the large number 292.
 
pi - log(23.141) = .000013282...
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

Similar threads

  • · Replies 7 ·
Replies
7
Views
2K
Replies
10
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
6
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
9
Views
6K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
12K