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Sig Fig

  1. Sep 5, 2006 #1
    If I had ((9-8.8))/8.8 how many sig figs would my answer have
  2. jcsd
  3. Sep 5, 2006 #2
    Only one sig fig. Since 9-8.8 = 0. and 0./8.8 = 0.

    On a side note: sig figs are really funny. You use 'em in high school but you never really use 'em afterwards (OK, maybe in chemistry but that's it).
    Last edited: Sep 5, 2006
  4. Sep 5, 2006 #3
    Sig figs were my least favorite part of physics.
  5. Sep 6, 2006 #4


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    Is the "9" a measured quantity or counted? If measured, then the fact that you only give one figure means it has only one significant figure- it could be anywhere between 8.5 and 9.5. If counted, then it is exact and can have any number of significant figures.

    In the first case, as swapnil said, it is (9- 9)/8.8= 0

    In the second, (9.0- 8.8)/8.8= 0.2/8.8= 0.023 (or, better, 2.3 x 10-2. The result has 2 significant figures because the "measured quanities", the "8.8"s have 2 significant figures.
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