Question

An experiment to compare the tension bond strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during mixing) to that of unmodified mortar resulted in x = 18.13 kgf/cm2 for the modified mortar (m = 42) and y = 16.83 kgf/cm2 for the unmodified mortar (n = 32). Let μ1 and μ2 be the true average tension bond strengths for the modified and unmodified mortars, respectively. Assume that the bond strength distributions are both normal.

An experiment to compare the tension bond strength of polymer latex modified mortar (Portland cement mortar to which polymer latex emulsions have been added during mixing) to that of unmodified mortar resulted in x = 18.13 kgf/cm2 for the modified mortar m = 42) and y = 16.83 kgrom 2 for the unmodified mortar (n = 32). Let μ1 and μ2 be the true average tension bond strengths for the modified and unmodified mortars, respectively. Assume that the bond strength distributions are both normal. (a) Assuming that σ1-1.6 and σ2-1.3, test H0: μι-μ2-0 versus Ha: μι-μ2 > 0 at level 0.01 Calculate the test statistic and determine the P-value. (Round your test statistic to two decimal places and your P-value to four decimal places.) Show Question Details P-value - (b) Compute the probability of a type II error for the test of part (a) when μ1-μ2-1. (Round your answer to four decimal places.) (c) Suppose the investigator decided to use a level 0.05 test and wished β = 0.10 when μι-μ2-1. If m-42, what value of n is necessary? (Round your answer up to the nearest whole number.) n2

Answer 1

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Since tis is igh tailed test, P-value is P-valuue plz3.8S) こ0.000 P-alue sziJ is less than o.o ,»ject hutl hypothesis enence boue -the means of the tuo gos Since The toue differ b) By definitions, he paolabilty of gpe s is Foom Paot la) 0.33 2.2.33 ף 0.01 Substrlute -he known Vale s, 2.33 0 337 Ó / 2.33-2.9673 φ(-0.63) 드 0.2628 is o.2628

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