<PRE><B>Question 1162332</B>
This has SE of sp*( sqrt((1/n1)+(1/n2)))
sp^2 is  (n1-1)s1^2+(n2-1)s2^2 divided by (n1+n2-2)
=22*10.3+29*4.2 divided by 51
=6.831
sqrt of that is sp or 2.614
SE is 2.614((1/23)+(1/30))=0.7245

t=diff in means/SE
=-11/0.7245=-15.19

I used art first and had a negative value; if one used economics first, it would be positive.</PRE>