Question 1189908
Ho: mu boy=mu girl
Ha: mu boy NE mu girl
alpha=0.05 p{reject Ho|Ho true}
test is 2 sample t-test
df=98
critical value is 1.985
calculation t=(diff means/SE)
=(67.4-62.8)/sqrt (s1^2/n1)+(s2^2/n2))
=4.6/sqrt [(25/50+(21.16/50)]
=4.6/.96=4.79
reject Ho and conclude there is a difference between the two at the 0.05 level.
p-value <0.0001
-
For difference of 3,
mu boy-mu girl <=3
mu boy-mu girl NE>=3
t-value is 3/0.96=3.125, so reject that hypothesis and say that the difference is greater than 3.