A mixture of pulverized fuel ash and Portland cement to be used for grouting should have a compressive strength of more

[answerhappygod]

A Mixture Of Pulverized Fuel Ash And Portland Cement To Be Used For Grouting Should Have A Compressive Strength Of More 1 (55.96 KiB) Viewed 121 times

A mixture of pulverized fuel ash and Portland cement to be used for grouting should have a compressive strength of more than 1300 KN/m2. 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 u = 59. Let u denote the true average compressive strength. (a) What are the appropriate null and alternative hypotheses? O HO <1300 versus H: 1300 OH = 1300 versus H, 1300 HH = 1300 versus H. : > 1300 O H > 1300 versus H, x= 1300 O H:= 1300 versis H. : 4 < 1300 (b) Let X denote the sample average compressive strength for n = 17 randomly selected specimens. Consider the test procedure with test statistic and rejection region 2 1331.26. What is the probability distribution of the test statistic when Ho is true? Indicate your answers in the form Nuu). NI what is the probability of a type I error for the test procedure? (Glve answer accurate to 4 decimal places.) (c) What is the probability distribution of the test statistic when = 1350? Indicate your answers in the form Nuo). NG . Using the test procedure of part (b), what is the probability that the mixture will be judged unsatisfactory when in fact I = 1350 (a type II error)? (Give answer accurate to 4 decimal places.) (d) How would you change the test procedure of part (b) to obtain a test with significance level.05? (Round to the nearest Integer.) set the rejection region to x2 What impact would this change have on the error probability of part (C)? (Glve answers accurate to 4 decimal places.) (1350) = 1 (e) Consider the standardized test statistic Z = (1 - 1300/(0/7). What are the values of corresponding to the rejection region of part (b)? (Give answers accurate to 2 decimal places.) z>