Arsenic blood concentrations in healthy people are Normally distributed with mean µ = 3.2 µg/dl and standard deviation o = 1.5 µg/dl. Some areas are known to have naturally elevated concentrations of arsenic in the ground and water supplies. (a) We seek proof against the claim that u = 3.2. If the claim is true, what is the sampling distribution of the mean blood arsenic concentration x in many samples of 25 adults? (N(_,_).) Sketch the density curve of this distribution. (Sketch a Normal curve, then mark the axis using what you know about finding the mean and standard deviation on a Normal curve.) (b) Assume the first sample's data gives x = 3.35 ug/dl. Mark this point on the axis of your sketch. Assume the second sample gives x = 3.75 µg/dl. Mark this point on your sketch. (c) The sample mean x =. the right tail of the curve when the sample mean x %3D %3D lies far out towards lies close to the centre. If the population mean is µ, finding a value similar would not be too surprising, but x = is much less likely, implying that µ = to x =

Arsenic blood concentrations in healthy people are Normally distributed with mean µ = 3.2 µg/dl and standard deviation o = 1.5 µg/dl. Some areas are known to have naturally elevated concentrations of arsenic in the ground and water supplies. (a) We seek proof against the claim that u = 3.2. If the claim is true, what is the sampling distribution of the mean blood arsenic concentration x in many samples of 25 adults? (N(_,_).) Sketch the density curve of this distribution. (Sketch a Normal curve, then mark the axis using what you know about finding the mean and standard deviation on a Normal curve.) (b) Assume the first sample's data gives x = 3.35 ug/dl. Mark this point on the axis of your sketch. Assume the second sample gives x = 3.75 µg/dl. Mark this point on your sketch. (c) The sample mean x =. the right tail of the curve when the sample mean x %3D %3D lies far out towards lies close to the centre. If the population mean is µ, finding a value similar would not be too surprising, but x = is much less likely, implying that µ = to x =

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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