# IS-5 - We are told that in September 2005 x-bar daily is...

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OM 335 Bagchi Name: SOLUTION _ Individual Homework-5 Consider the cases Quality Wireless (A) and (B). Assume that call center performance during the month of September 2005 is continuing at the improved level with a mean of 79.50 and a standard deviation of 16.86. (1) What is the probability of observing ten days that average 86.6 or more? Show your work. Let x-bar daily be the daily average hold time and x-bar 10-day be the ten-day daily average hold time (= the average of ten daily averages).
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Unformatted text preview: We are told that in September 2005, x-bar daily is Normal(mean = 79.5, std. dev. = 16.86). It follows that x-bar 10-day is Normal(mean = 79.5, std. dev. = 16.86/√(10) = 5.33). So, P(x-bar 10-day ≥ 86.6) = P(z ≥ (86.6 – 79.5)/5.33 = 1.33) = 0.0915 . (2) What is the probability of observing ten days that average 74.4 or less? Show your work. P(x-bar 10-day ≤ 74.4) = P(z ≤ (74.4 – 79.5)/5.33 = - 0.957) = 0.1693 . 1...
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## This note was uploaded on 04/20/2011 for the course OM 335 taught by Professor Jonnalagedda during the Spring '08 term at University of Texas.

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