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A distribution of exam scores has a mean of u=52 and standard deviation of 6. WHat is the z-score for the exam score X=61?

a.z=+0.5
b.z=+1.5
c.z=+2.
d. z=-1.5

1 Answer

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Final answer:

The z-score for an exam score of X=61, with a distribution mean (μ) of 52 and a standard deviation (σ) of 6, is calculated to be +1.5, indicating that the score is 1.5 standard deviations above the mean.

Step-by-step explanation:

The question asks for the calculation of a z-score for a given exam score using the mean and standard deviation of the distribution of exam scores. To find the z-score, we use the formula:

z = (X - μ) / σ

Where X is the exam score, μ is the mean, and σ is the standard deviation. Given μ = 52 and σ = 6 for the distribution, and X = 61 for the exam score, we can substitute these values into the formula to find:

z = (61 - 52) / 6

z = 9 / 6

z = 1.5

Therefore, the correct answer is b. z = +1.5, meaning the exam score of 61 is 1.5 standard deviations above the mean.

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