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In a sample of scores, a score that is -8 point(s) from the mean corresponds to z = -1.33. What is the standard deviation?

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Final answer:

The standard deviation of the sample is calculated using the z-score formula. With a score of -8 from the mean corresponding to a z-score of -1.33, we find that the standard deviation is approximately 6.02.

Step-by-step explanation:

To find the standard deviation, we can use the provided z-score and the distance of the score from the mean. A z-score (z) represents the number of standard deviations a score (x) is from the mean (μ). The formula for a z-score is given by:

z = (x - μ) / σ

Where:

  • x is the score
  • μ is the mean
  • σ is the standard deviation

In this case, we have a score that is 8 points below the mean, which corresponds to a z-score of -1.33. Plugging these values into the formula gives us:

-1.33 = (-8) / σ

To solve for σ, we multiply both sides by σ and then divide by -1.33:

σ = -8 / -1.33

σ ≈ 6.02

Therefore, the standard deviation of the sample is approximately 6.02.

User Arnaud Gourlay
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