Question 1156893
Ho: salary = $40K
Ha: it isn't
alpha=0.05 P{reject Ho|Ho true}
test stat is a t(0.975, df=19)*s/sqrt(n), t is 2.09
t=(43288-40000)/4000/sqrt(20)
=3288*sqrt(20/4000
=3.68
conclude the average salary of $40,000 is not correct.

one sample proportion
Ho: percentage is 0.30 or fewer
Ha: percentage is >0.30
reject Ho if z>1.645
p hat is 0.36
z=(0.36-0.30)/sqrt (0.3*0.7/200)
=0.06/0.0324
=1.85
reject Ho
evidence supports claim that proportion is more than 0.30