Complete the statement. Round your answer to the nearest thousandth.In a population that is normally distributed with mean 36 and standard deviation 16, the bottom 20% of the values are those less than ___.
Q. Complete the statement. Round your answer to the nearest thousandth.In a population that is normally distributed with mean 36 and standard deviation 16, the bottom 20% of the values are those less than ___.
Find z-score for 20%: To find the value that corresponds to the bottom 20% of the population, we need to use the z-score table to find the z-score that corresponds to a cumulative probability of 0.20.
Lookup z-score in table: Looking up the z-score for a cumulative probability of 0.20 in the z-score table, we find that the z-score is approximately −0.84.
Use z-score formula: Now we use the z-score formula to find the value: X=μ+zσ, where X is the value we are looking for, μ is the mean, z is the z-score, and σ is the standard deviation.
Plug in values: Plug in the values: X=36+(−0.84)(16).
Calculate value: Calculate the value: X=36−13.44.
Round to nearest thousandth:X=22.56, but we need to round to the nearest thousandth.
Round to nearest thousandth:X=22.56, but we need to round to the nearest thousandth.Rounded to the nearest thousandth, the value is 22.560.
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