Question

An article described an experiment to determine the effect of air voids on percentage retained strength of asphalt. For purposes of the experiment, air voids are controlled at three levels; low (24%), medium (46%), and high (68%). The data are shown in the following table.Air VoidsRetained StrengthLow106901039079889295Medium8069949170838783High7880626976856985Do the different levels of air voids significantly affect mean retained strength? Use α = 0:01.You are given that SSTreatments = 1230:25, SST = 2786.Be sure to show all your work including stating the appropriate hypotheses, constructing theANOVA table to obtain the test statistic, computing the critical value and your conclusion

Answer 1

Hypothesis:

H0 : There is no mean difference of treatments

Ha : There is at least one mean is different

Test:

formulas:

the result is significant at P<0.01 , we reject H0 that is at least one mean is different