Question

strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during miing) to that o unmodified mortar resulted in x 18.16 kgt/cm2 for the modified mortar (m 42) and y tension bond strengths for the modified and unmodified -16.87 kgf/cm2 for the unm dined mortar (n = 30). Let μ1 and», be the true average mortars, respectively. Assume that the bond strength distributions are both normal. (a) Assuming that σ1 1.6 and σ2-1.3, test HO-Mg-H2-0 versus Ha: μ1-R2 > 0 at level 0.01. Calculate the test statistic and determine the P-value. (Round your test st P-value a State the conclusion in the problem context Reject Mo. The data does not suggest that the difference in average tension bond strengths exceeds 0. Reject Hor The data suggests that the difference in average tension bond strengths exceeds o Fail to reject Ho. The data does not suggest that the difference in average tension bond strengths exceeds from O O Fail to reject Mo. The data suggests that the difference in average tension bond strength, exceeds 0. (b) compute the probability of a type 1I error for the test of part (a) when (Round your answer to four decimal places.) (c) Suppose the investigator decided to use a level 0.05 test and wished β " o. 10 when μ2-1. If m·42, hat value of o is necessary? (Round your answer up to ehe nearest whole number)

Answer 1

a)

reject Ho ; the data suggests.........

b)

c)

n=31