A population is normally distributed with mean 120 and standard deviation 30. Determine the probability that a sample of size 25 will have a mean between 110 and 125. round the z-value to two places past the decimal and use the standard normal table to find areas under the standard normal curve.
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Step 1
Given: Population mean (μ) = 120 Population standard deviation (σ) = 30 Sample size (n) = 25 Calculate z1: \( z1 = \frac{110 - 120}{\frac{30}{\sqrt{25}}} = \frac{-10}{6} = -1.67 \) Calculate z2: \( z2 = \frac{125 - 120}{\frac{30}{\sqrt{25}}} = \frac{5}{6} = 0.83 Show more…
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