Complete the statement. Round your answer to the nearest thousandth.In a population that is normally distributed with mean 66 and standard deviation 20, the bottom 40% 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 66 and standard deviation 20, the bottom 40% of the values are those less than ___.
Find z-score for 40\%: First, we need to find the z-score that corresponds to the bottom 40% of a normal distribution.
Calculate z-score: Using a z-table, we find that the z-score for the bottom 40% is approximately −0.25.
Use z-score formula: Now, we use the z-score formula: z=σX−μ, where X is the value we're looking for, μ is the mean, and σ is the standard deviation.
Solve for X: We rearrange the formula to solve for X: X=z⋅σ+μ.
Plug in values: Plug in the values: X=−0.25×20+66.
Calculate X: Calculate the value: X=−5+66.
Final result:X=61.
More problems from Find values of normal variables