Oil pipes ~ Oil field pipes are internally coated in order to prevent corrosion. Researchers investigated the influence that coating may have on the surface roughness of oil field pipes. A random sample of 20 sections of coated interior pipe was scanned with a probe and the standard deviation of the measurements was 0.52 micrometers. 1. If the researchers want to construct a 95% confidence interval with a margin of error of no more than 0.15micrometer, how large of a sample must they take?

Oil pipes ~ Oil field pipes are internally coated in order to prevent corrosion. Researchers investigated the influence that coating may have on the surface roughness of oil field pipes. A random sample of 20 sections of coated interior pipe was scanned with a probe and the standard deviation of the measurements was 0.52 micrometers. 1. If the researchers want to construct a 95% confidence interval with a margin of error of no more than 0.15micrometer, how large of a sample must they take?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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