Complete the statement. Round your answer to the nearest thousandth.In a population that is normally distributed with mean 87 and standard deviation 11, the bottom 70% 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 87 and standard deviation 11, the bottom 70% of the values are those less than ___.
Find Z-score for 70%: To find the value that separates the bottom 70% from the rest, we need to use the z-score table to find the z-score that corresponds to a cumulative probability of 0.70.
Lookup Z-score in table: Looking up 0.70 in the z-score table, we find that the closest z-score is approximately 0.52.
Calculate X using formula: Now, we use the z-score formula to find the value X: Z=standard deviationX−mean. Rearranging the formula to solve for X gives us X=Z×standard deviation+mean.
Plug in values for X: Plugging in the values, we get X=0.52×11+87.
Round to nearest thousandth: Calculating this, X=5.72+87.
Round to nearest thousandth: Calculating this, X=5.72+87.So, X=92.72. But we need to round 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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