value of pi and 22/7

[Steven D'Aprano]

On Sat, 18 Jun 2016 09:49 am, Ian Kelly wrote:

> If I tell you that the speed of light is 300,000,000 m/s, do you think
> that measurement has 9 significant digits? If you do, then you would be
> wrong.

Hmmm.

If I tell you that some physical phenomenon [let's call it the speed of
light] is 299,999,999 m/s, how many significant digits would I be using?

What if I tell you that it's 300,000,001 m/s?

What if the figure to nine significant digits *actually is* three followed
by eight zeroes?

For all that it is in widespread use, I think the concept of "significant
figures" is inherently ambiguous.



-- 
Steven