Recent content by rogo0034

  1. R

    What proportion is defective, with 99% confidence interval

    Not entirely sure how to set this up as I'm used to comparing a population with sample statistics. This seems as if it would simplify things, though in stats, I've found that simplicity only makes you second guess yourself. That's where I'm at. Any Ideas? advice?
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    What proportion is defective, with 99% confidence interval

    Homework Statement Homework Equations The Attempt at a Solution
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    Show how the variance decrease as degrees of freedom/sample size get bigger

    Homework Statement Homework Equations The Attempt at a Solution I'm confused actually how to go about this. Sounds very simple, but when i do what they suggest, 'first, find the variance of (n-1)s2/σ2 i get larger variances rather than smaller, which makes no sense. should...
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    Prob. for Difference of mean, single finite pop.

    A: .0119 and .0024 respectively, for the prob of being over 20, is this at all right? B:So I put them each into the central limit theorem and got: .1892 for the first and .1591 for the second
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    Prob. for Difference of mean, single finite pop.

    not entirely sure what to do here, i mean I've gotten the Variance for each, 78.125 & 50, and then... I'm confused because it's coming from one population, not two. hmmf.
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    Prob. for Difference of mean, single finite pop.

    Homework Statement Homework Equations The Attempt at a Solution
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    Variance of a weighted population

    Got it! thanks, that was easier
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    Variance of a weighted population

    Homework Statement Homework Equations The Attempt at a Solution Was able to get the population mean of 5.3 with 4*.2 + 5*.4 + 6*.3 + 7*.1 But for some reason I'm drawing blank for the variance (which i guess is .81)
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    Finding the prob. in a continuous uniform distribution (z values)

    ahhhh, for some reason i was thinking this was a bell curve the whole time. But, because of that realization, i found the formulas for mean and SD, and plugged them into the formula originally given. Sorry the quality is terrible, but here's what i got.
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    Approximate the Prob. in a normal distribution of a binomial

    See, i was having trouble determining when to use the Continuity Correction in the problems, and i guess i still am. but i was able to match my answer with the given one from the back of the book when I stopped using it. however, the second problem doesn't match, even after using the new...
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    Approximate the Prob. in a normal distribution of a binomial

    Homework Statement Homework Equations The Attempt at a Solution
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    Finding the prob. in a continuous uniform distribution (z values)

    Great, i finished the sections homework without any issues, took no time at all, except for this one problem, I must be over thinking it...?? this problem seems like it should be so simple.
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    Finding the prob. in a continuous uniform distribution (z values)

    I'm assuming the mean is 3 because it is a uniform distribution 1 through 5, which would make the mean three... right? (two units on each side, central tendency). I don't have any more information about this problem than is given, but since it is a normal uniform distribution, it should fit...
  14. R

    Finding the prob. in a continuous uniform distribution (z values)

    OK, so this isn't helping yet, I'm still under the impression that in order to solve this problem, i need the mean (which I'm assuming is 3), and the standard deviation from the mean (which I'm at a loss for). Anyone able to help explain this better, it's the first question in my homework and i...
  15. R

    Finding the prob. in a continuous uniform distribution (z values)

    Here's what we are given in one of the examples helping to explain it to us. I put in the formula for Z because if i had the standard deviation and mean, this would be extremely simple (for me)