Complete the statement. Round your answer to the nearest thousandth.In a population that is normally distributed with mean 41 and standard deviation 4, 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 41 and standard deviation 4, the bottom 20% of the values are those less than ___.
Find z-score for bottom 20%: First, we need to find the z-score that corresponds to the bottom 20% of a normal distribution.
Use z-score formula: Using a z-table, we find that the z-score for the bottom 20% is approximately −0.842.
Rearrange formula for X: Now, we use the z-score formula: z=standard deviationX−mean, where X is the value we're looking for.
Plug in values: We rearrange the formula to solve for X: X=z×standard deviation+mean.
Calculate X value: Plug in the values: X=−0.842×4+41.
Calculate X value: Plug in the values: X=−0.842×4+41.Calculate the value of X: X=−3.368+41.
Calculate X value: Plug in the values: X=−0.842×4+41.Calculate the value of X: X=−3.368+41. X=37.632, which we round to the nearest thousandth as 37.632.
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