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MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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The U.S. Department of Defence Pentagon structure contains a total of 691water fountains! Let's say that you are on a tour of the Pentagon and you happen to know that each fountain was recently tested for lead content in the water provided by the fountain and the average lead content for all 691 fountains was found to be 12 ppb with a standard deviation of 3.2 ppb. You are concerned that it would be unsafe to drink water with a lead level of 20 ppb or higher. If you stop and drink at a randomly chosen fountain, what is the probability that the water it dispenses has 20 ppb or higher lead content (assuming the lead contents of the fountains are normally distributed )?
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