Problem

The mean of a normally distributed data set is 75 with a standard deviation of 5 . Find the data value that is greater than 8% of the data.
Click here to see page 1 of the table for areas under the standard normal curve.
Click here to see page 2 of the table for areas under the standard normal curve.

The data value that is greater than 8% of the data is .
(Round to the nearest whole number as needed.)

Answer

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Answer

68 is the data value that is greater than 8% of the data.

Steps

Step 1 :Find the z-score that corresponds to the 8% percentile. Since the problem asks for the data value that is greater than 8% of the data, we need to look at the lower tail of the distribution.

Step 2 :Use a standard normal distribution table to find the z-score that corresponds to the 8% percentile. The z-score is approximately -1.41.

Step 3 :Use the z-score formula to find the corresponding data value. The z-score formula is Z=Xμσ, where Z is the z-score, X is the data value, μ is the mean, and σ is the standard deviation.

Step 4 :Rearrange the formula to solve for X: X=Zσ+μ.

Step 5 :Substitute the values into the formula: X=1.415+75.

Step 6 :Calculate the above expression: X=7.05+75.

Step 7 :Round to the nearest whole number: X=68.

Step 8 :68 is the data value that is greater than 8% of the data.

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