The Environmental Protection Agency is concerned with the problem of setting criteria for the amounts of certain toxic chemicals to be allowed in freshwate and rivers. A common measure of toxicity for any pollutant is the concentration of the pollutant that will kill half of the test species in a given amount of tim (usually 96 hours for fish species). This measure is called LC50 (lethal concentration killing 50% of the test species). In many studies, the values contained natural logarithm of LC50 measurements are normally distributed, and, hence, the analysis is based on In(LC50) data. Studies of the effects of copper on a certain species of fish (say, species A) show the variance of In(LC50) measurements to be around 0.75 with concentrat measurements in milligrams per liter. If n = 12 studies on LC50 for copper are to be completed, find the probability that the sample mean of In(LC50) will d from the true population mean by no more than 0.5. (Round your answer to four decimal places.)

The Environmental Protection Agency is concerned with the problem of setting criteria for the amounts of certain toxic chemicals to be allowed in freshwate and rivers. A common measure of toxicity for any pollutant is the concentration of the pollutant that will kill half of the test species in a given amount of tim (usually 96 hours for fish species). This measure is called LC50 (lethal concentration killing 50% of the test species). In many studies, the values contained natural logarithm of LC50 measurements are normally distributed, and, hence, the analysis is based on In(LC50) data. Studies of the effects of copper on a certain species of fish (say, species A) show the variance of In(LC50) measurements to be around 0.75 with concentrat measurements in milligrams per liter. If n = 12 studies on LC50 for copper are to be completed, find the probability that the sample mean of In(LC50) will d from the true population mean by no more than 0.5. (Round your answer to four decimal places.)

Advanced Engineering Mathematics

10th Edition

ISBN:9780470458365

Author:Erwin Kreyszig

Publisher:Erwin Kreyszig

Chapter2: Second-order Linear Odes

Section: Chapter Questions

Problem 1RQ

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