Math

LongLast Inc. produces car batteries. The mean life of these batteries is 60 months. The distribution of the battery life closely follows the normal probability distribution with a standard deviation of 8 months.

As part of its testing program, LongLast tests a sample of 25 batteries.

What is the standard error of the mean?

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asked by Mark
  1. try:
    http://davidmlane.com/hyperstat/z_table.html

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    posted by Damon
  2. That does not help calculate the standard of error.

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    posted by Mark
  3. http://www.miniwebtool.com/standard-error-calculator/

    8/sqrt(25) = 8/5 = 1.6

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    posted by Damon

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