Hello
Use this formula
avg(field1) + field2 + field3 + field4
before that make the fields datatype to that of Numbers
Also Read the Link Below
http://enterprise-solutions.swits.net/infopath2003/article.php?t=avg-function-in
fopath&c=infopath2003
It gives more information

Signature
Kalyan G Reddy - INFOPATH MVP 2007
http://www.ggktech.com
> how to make the avarage for four fields