An atomic absorption method for the determination of theamount of iron present in used jet engine oil was foundfrom pooling 30 triplicate analyses to have a standard de-viation s = 3.6 µg Fe/mL. If s is a good estimate of o, cal-culate the 95 and 99% confidence intervals for the result18.5 µg FelmL if it was based on (a) a single analysis, (b)the mean of two analyses, and (c) the mean of four analyses.

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An atomic absorption method for the determination of the amount of iron present in used jet engine oil was found from pooling 30 triplicate analyses to have a standard de- viation s = 3.6 ug Fe/mL. If s is a good estimate of o, cal- culate the 95 and 99% confidence intervals for the result 18.5 ug Fe/mL if it was based on (a) a single analysis, (b) the mean of two analyses, and (c) the mean of four analyses.

An atomic absorption method for the determination of the amount of iron present in used jet engine oil was found from pooling 30 triplicate analyses to have a standard de- viation s = 3.6 ug Fe/mL. If s is a good estimate of o, cal- culate the 95 and 99% confidence intervals for the result 18.5 ug Fe/mL if it was based on (a) a single analysis, (b) the mean of two analyses, and (c) the mean of four analyses.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter25: Instruments For Optical Spectrometry

Section: Chapter Questions

Problem 25.22QAP

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