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Statistical Problem in Analytical Chem

  1. Sep 16, 2011 #1
    1. The problem statement, all variables and given/known data

    The following set of analyses represent concentrations of chloride in blood serum (meq/L): 103,106,107,114. One value appears suspect. Determine if it can be rejected at the 95% confidence level.

    2. Relevant equations
    Mean

    Standard Deviation:
    standard-deviation-2.png

    http://www.sjsu.edu/faculty/gerstman/StatPrimer/t-table.pdf"

    Degrees of Freedom = n -1 (n in this case being 4)

    Confidence Interval:
    CI.jpg


    3. The attempt at a solution

    So I found the mean to 107.5, and the standard deviation to be 4.65 (If anyone wants to see how I did this, just let me know).

    Then using the table, I found that t95 = 3.182 (using that there are 3 degrees of freedom)

    Using the confidence interval formula, I calculated the answer to be 107.5 +/- 7.40.

    I'm stuck from here and in fact have no idea if I even started this problem properly. PLEASE HELP :(
     
    Last edited by a moderator: Apr 26, 2017
  2. jcsd
  3. Sep 17, 2011 #2
    Re: Chemistry Problem -- Analytical Chem

    Anyone? :( I'm super desperate
     
  4. Sep 17, 2011 #3
    Re: Chemistry Problem -- Analytical Chem

    Actually -- would it be possible to simply use Grubb's test?
     
    Last edited: Sep 17, 2011
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