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Homework Help: Uncertainties and Averages

  1. Oct 14, 2006 #1
    If an average of three numbers with equal uncertainties is taken, does the average have an uncertainty of the sum of the absolute uncertainties of the three numbers?
    e.g. (3.0 +/- 0.1) + (6.0 +/- 0.1) + (9.0 +/- 0.1)/3 = 6.0 +/- 0.3?
    This makes sense to me because the three in the denominator has no uncertainty.

    p.s. I know this may not seem like it belongs in this forum ( :confused: ), though uncertainties are scientific calculations, so...
     
  2. jcsd
  3. Oct 14, 2006 #2

    GCT

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    Take the square root of the sum of the squares of the values.
     
  4. Oct 15, 2006 #3
    What values, the uncertainties or the numbers? What will that give me? The uncertainty?
     
  5. Oct 15, 2006 #4

    GCT

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    The uncertainties, it's going to give you the absolute uncertainty.
     
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