1. Suppose that IQ scores have a bell-shaped distribution with a mean of 100 and a standard deviation of 14. Using the empirical rule, what percentage of IQ scores are between 58 and 142? 2.A quality control inspector has drawn a sample of 1414 light bulbs from a recent production lot. Suppose 30%30% of the bulbs in the lot are defective. What is the probability that exactly 22 bulbs from the sample are defective? Round your answer to four decimal places.
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To use the empirical rule, we need to know the standard deviation and mean of the distribution. In this case, the mean is 100 and the standard deviation is 14. The empirical rule states that for a bell-shaped distribution: - Approximately 68% of the data falls Show more…
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