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Significant figures ?

  1. Mar 26, 2005 #1
    o:) ok...

    So We got 2 number (i) 34500000000 & (ii) 30.4 <both to 3 sig fig>

    is zero considered a significant figure in this case...? If it is, then why do we include the zeros in 34500000000, if it is not, why, 30.4 and not 30.44?
  2. jcsd
  3. Mar 26, 2005 #2
    zero in the middle of non-zero numbers is always counted as a sigfig
    but if it's the last number.. then it may or may not be counted as sigfig
    if it's the first one, it is not a sigfig (e.g 0.0002 --> 1 sigfig)
  4. Mar 26, 2005 #3


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    The basic idea behind the rules is that if zero is merely acting as a place-holder, it isn't counted as significant. The rules rely partially on convention to remove ambiguity, so there really is no substitute for just learning the http://www.swt.edu/slac/math/SigFigur.html [Broken].
    As tigger said, (i) is ambiguous as written. See Rule 5 in the link.
    Last edited by a moderator: May 2, 2017
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