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Example 114
Example 114: Butt-dialing 911 is a growing problem. In New York City, a 2012 report stated that 40% of calls made to 911 were dialed in error from cell phones. The report looked at a sample of 743,000 calls handled by NYC’s 911 operators. Construct a 98% confidence interval estimate of the true proportion of NYC 911 calls that are made in error. Before this report the mayor of NYC claimed that more than 45% of the calls made to 911 were due to “butt-dialing.” Did this report contradict the mayor’s claim?
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