2) The music industry must adjust to the growing practice of consumers downloading songs instead of buying CDs. It therefore becomes important to estimate the proportion of songs that are currently downloaded. How many randomly selected song purchases must be surveyed to determine the percentage that were obtained by downloading? Assume that we want to be 97% confident that the sample percentage is within two percentage points of the true population percentage of songs that are downloaded. a. Calculate the needed sample size if a previous study suggests that 95% of songs are downloaded. b. Calculate the needed sample size if no estimate of the percentage of songs that are downloaded is not available.
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This means that the margin of error is 2%. We are also given that a previous study suggests that 95% of songs are downloaded. We can use this information to calculate the needed sample size. Show more…
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