Assume that the helium porosity (in percentage) of coal samples taken from any particular seam is normally distributed with true standard deviation 0.77.(a) Compute a 95% CI for the true average porosity of a certain seam if the average porosity for 21 specimens from the seam was 4.85. (Round your answers to two decimal places.)4.52075.1793(b) Compute a 98% CI for true average porosity of another seam based on 20 specimens with a sample average porosity of 4.56. (Round your answers to two decimal places.)4.164.96(c) How large a sample size is necessary if the width of the 95% interval is to be 0.48? (Round your answer up to the nearest whole number.)40specimens(d) What sample size is necessary to estimate true average porosity to within 0.23 with 99% confidence? (Round your answer up to the nearest whole number.)40specimens

( d ) For the given data Find n =?

Answered: (d) What sample size is necessary to…

(d) What sample size is necessary to estimate true average porosity to within 0.23 with 99% confidence? (Round your answer up to the nearest whole number.) 40 X specimens

Algebra: Structure And Method, Book 1

(REV)00th Edition

ISBN:9780395977224

Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole

Publisher:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole

Chapter12: Quadratic Functions

Section12.6: Solving Problems Involving Quadratic Equations

Problem 1.3E

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