Question 1195846
Assume normality, random sampling, and sd of sample is unbiased estimator of sd population.
Ho: mu new=mu old
Ha: mu new NE mu old
alpha=0.05 p(reject Ho|Ho true}
test is a t(0.975, df=35)
critical value is |t|> 2.031
t=(50-55)/12/sqrt(36)
=-5*6/12
=-2.5
reject Ho; the evidence supports that the new system is faster than the old one. p-value=0.017.