For a population with \( \mu=25 \) and \( \sigma=5 \), we would expect \( 90 \% \) of all \( \bar{x} \) 's calculated from \( n=35 \) to fall between \( \square \) and \( \square \) (Round to two decimals.)
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To find the interval containing 90% of the sample means (\( \bar{x} \)) when \( n = 35 \), we can use the Central Limit Theorem. The standard error \( SE \) of the mean can be calculated using the formula: \[ SE = \frac{\sigma}{\sqrt{n}} = \frac{5}{\sqrt{35}} \approx 0.845 \] For a 90% confidence interval, we can find the critical z-value, which is approximately 1.645 for a one-tailed test (because we have \( 5\% \) in each tail). Thus, we can calculate the margin of error: \[ \text{Margin of Error} = z \times SE = 1.645 \times 0.845 \approx 1.39 \] Now, subtract and add this margin from the population mean (\( \mu = 25 \)): Lower limit: \[ 25 - 1.39 \approx 23.61 \] Upper limit: \[ 25 + 1.39 \approx 26.39 \] Thus, we would expect 90% of all sample means to fall between \( \text{23.61} \) and \( \text{26.39} \).