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Homework Help: Quick Question about uncertainty

  1. Mar 14, 2005 #1
    I'm doing a lab report right now, but am fuzzy on uncertainty in certain respects.

    I have something like

    d = 25 +/-2, d2 = 330 +/- 3, x = 55 +/- 6etc

    how do I calculate the uncertainty, in another quantity, if it's like this

    c = (d1 + d2)/x

    Basically, how do I calculate the +/- part in c?
  2. jcsd
  3. Mar 14, 2005 #2
    for both multiplication and division the uncertainties are added like this

    [tex] \frac{\Delta c}{c} = \frac{\Delta d_{1}}{d_{1}} + \frac{\Delta d_{2}}{d_{2}} + \frac{\Delta x}{x} [/tex]
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