Question 1181998
Ho: meanA <=mean B
Ha: mean A > mean B
alpha=0.05 P{reject Ho| Ho true}
test is a 2-sample t-test
reject Ho if t>1.675
test is a t (df=48)=(meanA-mean B)/sqrt (s1^2*/na)+(s2^2/(nb))
=(-2.5)/sqrt((9/20)+(4/30))
=-2.5/sqrt(0.583)
=-3.27
fail to reject Ho; indeed, the data themselves show that A has a a statistically  smaller mean than B.