A call centre would like to know the mean number of calls it receives during peak hours. The manager randomly selects 32 different one-hour periods and determines the number of calls for each. For this sample, x-bar equals 95 and s2 = 230. What is the mean number of calls per one-hour period during peak hours with a 99% confidence interval? 95 ± 2.68 95 ± 5.25 95 ± 6.90 95 ± 104.73
Added by Yvonne B.
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576. Margin of error = 2.576 * sqrt(230) / sqrt(32) = 6.90 Show more…
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