? asked in Science & MathematicsMathematics · 10 years ago

statistics question 10 point reward !?

small local company were asked what their annual salary was. For this group was $22,500, with a standard deviation of $1500.

96 confidence interval for the average annual salary of all employee of this company?

4 Answers

Relevance
  • 10 years ago
    Best Answer

    X : salary of employees

    xmean = 22500

    sx = 1500

    Pf(22500 - 1500*2.055< μx < 22500 + 1500*2.055) = 0.96

    Pf( 19417.5 < μx < 25582.5 ) = 0.96

  • None
    Lv 7
    10 years ago

    Look up a table of the single tail normal distribution to see how many standard deviations away from the mean will include 48% of the values. Then multiply this by 2 x $1500.

    Hint: 2 standard deviations from the mean includes 47.7 % of the data on one side, or 95.4% of all the data for both tails, so your answer should be just a little over $3000

  • 10 years ago

    Look up your z-table for 0.96 to get the z value (should be about 2). The 96% CI will be:

    22,500 +/- (1500 * z-value).

  • 10 years ago

    approx 2.0545 x 1500...so 22500 +- 3081.75 is the 96% range of salaries.

    Source(s): Me
Still have questions? Get your answers by asking now.