Problem+Post - J of Envir Engr 1995 785-790 suggests that...

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An economist wishes to estimate the average family income in a certain population. The population standard deviation is known to be $4,500, and the economist uses a random sample of size = 225. a. What is the probability that the sample mean will fall within $800 of the population mean? b. What is the probability that the sample mean will exceed the population mean by more than $600. Please describe in detail, as well as how the z-table values are determined. The article “Reliability of Domestic Waste Biofilm Reactors” (
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Unformatted text preview: J. of Envir. Engr., 1995: 785-790) suggests that substrate concentration (mg/cm^3) of influent to a reactor is normally distributed with = 0.30 and = 0.06. a. What is the probability that the concentration exceeds 0.40? b. What is the probability that the concentration is at most 0.25? c. How would you characterize the largest 10% of all concentration levels? Please describe in detail....
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This note was uploaded on 12/05/2011 for the course ECON 202 taught by Professor Woodland during the Spring '08 term at Eastern Michigan University.

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