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Calculate the following percentages for a z score of -1.61, with a tail of 5.37%:

a. What percentage of scores fall above the z score?
b. What percentage of scores fall between the mean and the z score?
c. What percentage of scores fall above a z score of 1.61?

User Muon
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1 Answer

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Final answer:

The z-score represents the number of standard deviations a data point is from the mean. To calculate the percentages for a z-score of -1.61 with a given tail percentage, subtract the tail percentage from 100% for scores above the z-score, subtract half the tail percentage from 50% for scores between the mean and the z-score, and subtract the percentage below the z-score from 100% for scores above a specific z-score.

Step-by-step explanation:

The z-score represents the number of standard deviations a data point is from the mean in a normal distribution. For a z-score of -1.61, we can use a standard normal distribution table to find the probabilities:

a. To find the percentage of scores above the z-score, we subtract the tail percentage from 100%. In this case, it would be 100% - 5.37% = 94.63%.

b. To find the percentage of scores between the mean and the z-score, we subtract the percentage below the z-score from 50%. In this case, it would be 50% - (5.37%/2) = 48.315%.

c. To find the percentage of scores above a z-score of 1.61, we subtract the percentage below the z-score from 100%. In this case, it would be 100% - (100% - 5.37%) = 5.37%.

User Esat
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