A mixture of pulverized fuel ash and Portland cement to be used for grouting should have...

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A mixture of pulverized fuel ash and Portland cement to be used for grouting should have a compressive strength of more than 1,300 KN/m. The mixture will not be used unless experimental evidence indicates conclusively that the strength specification has been met. Suppose compressive strength for specimens of this mixture is normally distributed with = 69. Let u denote the true average compressive strength. (a) What are the appropriate null and alternative hypotheses? Ho: = 1,300 Ha 1,300 Ho: H = 1,300 Ha: < 1,300 Hoi u > 1,300 Ha = 1,300 Ho t = 1,300 Ha u > 1,300 Ho: < 1,300 Ha = 1,300 (b) Let X denote the sample average compressive strength for n = 15 randomly selected specimens. Consider the test procedure with test statistic X itself (not standardized). What is the probability distribution of the test statistic when Ho is true? The test statistic has a binomial distribution. The test statistic has a normal distribution. The test statistic has a gamma distribution. The test statistic has an exponential distribution. If x = 1,340, find the P-value. (Round your answer to four decimal places.) P-value = 0.0206 Should Ho be rejected using a significance level of 0.01? reject Ho do not reject Ho (c) What is the probability distribution of the test statistic when = 1,350 and n = 15? The test statistic has an exponential distribution. The test statistic has a normal distribution. The test statistic has a binomial distribution. The test statistic has a gamma distribution. State the mean and standard deviation (in KN/m) of the test statistic. (Round your standard deviation to three decimal places.) mean standard deviation 1350 KN/m 19.598 X KN/m For a test with a = 0.01, what is the probability that the mixture will be judged unsatisfactory when in fact = 1,350 (a type II error)? (Round your answer to four decimal places.) 0.4109 You may need to use the appropriate table in the Appendix of Tables to answer this question. A mixture of pulverized fuel ash and Portland cement to be used for grouting should have a compressive strength of more than 1,300 KN/m. The mixture will not be used unless experimental evidence indicates conclusively that the strength specification has been met. Suppose compressive strength for specimens of this mixture is normally distributed with = 69. Let u denote the true average compressive strength. (a) What are the appropriate null and alternative hypotheses? Ho: = 1,300 Ha 1,300 Ho: H = 1,300 Ha: < 1,300 Hoi u > 1,300 Ha = 1,300 Ho t = 1,300 Ha u > 1,300 Ho: < 1,300 Ha = 1,300 (b) Let X denote the sample average compressive strength for n = 15 randomly selected specimens. Consider the test procedure with test statistic X itself (not standardized). What is the probability distribution of the test statistic when Ho is true? The test statistic has a binomial distribution. The test statistic has a normal distribution. The test statistic has a gamma distribution. The test statistic has an exponential distribution. If x = 1,340, find the P-value. (Round your answer to four decimal places.) P-value = 0.0206 Should Ho be rejected using a significance level of 0.01? reject Ho do not reject Ho (c) What is the probability distribution of the test statistic when = 1,350 and n = 15? The test statistic has an exponential distribution. The test statistic has a normal distribution. The test statistic has a binomial distribution. The test statistic has a gamma distribution. State the mean and standard deviation (in KN/m) of the test statistic. (Round your standard deviation to three decimal places.) mean standard deviation 1350 KN/m 19.598 X KN/m For a test with a = 0.01, what is the probability that the mixture will be judged unsatisfactory when in fact = 1,350 (a type II error)? (Round your answer to four decimal places.) 0.4109 You may need to use the appropriate table in the Appendix of Tables to answer this question.