CD Manufacturing Inc. wants the mean lengths of the "cuts" on a CD to be 170 seconds. This will allow the disk jockeys to have plenty of time for commercials within each 10-minute segment. Assume the distribution of the length of the cuts follows a normal distribution with a standard deviation of 11 seconds. Suppose that we select a sample of 25 cuts from various CDs sold by CRA CDs Inc. For answering the following questions always round z values to 2 decimal places. a) What is the probability that the sample means will be greater than 175 seconds? (Round your answer to 4 decimal places as needed) Probability: b) What is the probability that the sample means will be less than 169 seconds? (Round your answer to 4 decimal places as needed) Probability: c) What is the probability that the sample means will be greater than 169 but less than 175 seconds? (Round your answer to 4 decimal places as needed)
Added by Kayla R.
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Given σ = 11 seconds and n = 25, we have: SEM = 11 / √25 SEM = 11 / 5 SEM = 2.2 seconds Show more…
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