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Chebyshev's Theorem

  1. Oct 18, 2007 #1
    I know what the theorem states, but cant figure out how to input the data to make it work. Example

    BIG Corporation produces just about everything but is currently interested in the lifetimes of its batteries, hoping to obtain its share of a market boosted by the popularity of portable CD and MP3 players. To investigate its new line of Ultra batteries, BIG randomly selects Ultra batteries and finds that they have a mean lifetime of hours, with a standard deviation of hours. Suppose that this mean and standard deviation apply to the population of all Ultra batteries. Complete the following statements about the distribution of lifetimes of all Ultra batteries.

    According to Chebyshev's Theorem, at least 36% of the lifetimes lie between ___hrs & ___hrs

    According to Chebyshev's Theorem, at least ?% of the lifetimes lie between 719hrs & 1059hrs

    According to the empirical rule, Suppose the distribution is bell-shaped, approximately what % of the life-times lie between 719 hours & 1059 hrs?

    Suppose the distribution is bell-shaped. According to the empirical rule, approximately 68% of the lifetimes lie between ___hours & ____hrs?
  2. jcsd
  3. Oct 18, 2007 #2


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    You need to know the parameters ([itex]\mu, \sigma[/itex]) in terms of hours.
  4. Mar 1, 2009 #3
    yes, to clarify, you need to provide us first with the given MEAN and the given STANDARD DEVIATION before we can even begin to answer this problem. If you are not given that I do not know if you can solve this problem.
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