Recent content by Sir

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    Standard deviations and probabilities

    all right! I found the equation to govern this. let z be the number of standard deviations away from the mean ... u be the mean ... x be the value of a determination ... n be the number of determinations ... s be the standard deviation z = (| u - x | * (n)^(1/2)) / s
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    Standard deviations and probabilities

    Homework Statement Suppose a sample containing 0.600 ppm Selenium is analyzed by a method for which the standard deviation of the population is known to be 0.005 ppm. 1) What is the the probability that a single determination would return a value less than 0.590 ppm? 2) What is the probability...
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    What is the standard error of the mean in analytical chemistry?

    in my analytical chemistry review, this question cropped up. the first part was simple, but the second part has me confused to no end. I've tried playing around with the math as well as scouring my textbook for answers. help! what is the probability that a single determination of a value is...
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    Edit Avatar & Signature: Free or Paid?

    How does one edit their avatar and signature? Does it require a paid membership, or am I just too inept to find it in the CP?
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    Favorite Equation: Quadratic Formula - Solving for X

    \int_{-\infty}^{+\infty} e^{-x^{2}} = \sqrt{\pi}
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    Multivariate and vector calculus

    i'm about halfway through a multivariable and vectors course. we're about to start vectors, but for the multivariable part... know your integration. we've spent half a course so far in it.
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