Complete the statement. Round your answer to the nearest thousandth.In a population that is normally distributed with mean 54 and standard deviation 17, 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 54 and standard deviation 17, the bottom 20% of the values are those less than ___.
Find z-score: We need to find the z-score that corresponds to the bottom 20% of a normal distribution.
Use z-table: Looking up the z-score for the bottom 20% in a z-table, we find that it is approximately −0.84.
Apply z-score formula: Now we use the z-score formula: z=standard deviationX−mean. We need to solve for X, which represents the value we're looking for.
Solve for X: Plugging in the values we get: −0.84=17X−54.
Calculate left side: Multiplying both sides by 17 to solve for X gives us: −0.84×17=X−54.
Isolate X: Calculating the left side: −0.84×17=−14.28.
Calculate right side: Adding 54 to both sides to isolate X gives us: −14.28+54=X.
Round answer: Calculating the right side gives us: 39.72=X.
Round answer: Calculating the right side gives us: 39.72=X.We round our answer to the nearest thousandth, which doesn't change the value in this case since it's already at the thousandth place.
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