Complete the statement. Round your answer to the nearest thousandth.In a population that is normally distributed with mean 47 and standard deviation 25, 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 47 and standard deviation 25, the bottom 20% of the values are those less than ___.
Find z-score for 20\%: Find the z-score for 20\%. Using a z-table or calculator, the z-score for 20\% is approximately −0.842.
Use z-score formula: Use the z-score formula to solve for X. mean (μ): 47 standard deviation (σ): 25 z-score (Z): −0.842 Z=σX−μ −0.842=25X−47
Multiply by standard deviation: Multiply both sides by the standard deviation to isolate (X−μ).−0.842×25=X−47−21.05=X−47
Add mean to solve for X: Add the mean to both sides to solve for X.X=−21.05+47X=25.95
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