Complete the statement. Round your answer to the nearest thousandth.In a population that is normally distributed with mean 50 and standard deviation 20, 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 50 and standard deviation 20, the bottom 20% of the values are those less than ___.
Find z-score for 20%: We need to find the z-score that corresponds to the bottom 20% of a normal distribution.
Use z-table: Using a z-table, we find that the z-score for the bottom 20% is approximately −0.842.
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.
Plug in values: Plugging in the values we get: −0.842=20X−50.
Isolate X: Multiplying both sides by 20 to isolate X, we get: −0.842×20=X−50.
Do multiplication: Now we do the multiplication: −16.84=X−50.
Solve for X: Adding 50 to both sides to solve for X, we get: X=50−16.84.
Calculate final value: Finally, we calculate X: X=33.16.
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