InfoPath Dev

 I am relatively new to Infopath and have been struggeling with a problem.
I have a drop down field in a repeatable table and want to populate another field in the same table based on information in the first one.
I know how to filter an imported list from Sharepoint.
However, I only need 3 values in my list and was hoping this could be achieved without connection to an external connection, but using for example Rules instead.

Here is my form:

A drop down list with the manually created values:
 - More than 100
 - Less than 100
 - Equals 100

A textboks that will give
   a) 3,50  if the user chooses "More than 100" in the drop down list
   b) 2,90  if the user chooses "Less than 100" in the drop down list
   c) 3,00  if the user chooses "Equals 100" in the drop down list

Is it possible to solve this without using a data connection?

Certainly.  Just bind the dropdown box to a field in the repeating section, and give it 3,50, 2,90, and 3,00 as its three values, and "More than 100", "Less than 100" and "Equals 100" as the respective display names.

Then create a text box in your form that is bound to the same field as the dropdown box (go to "Data Source" in the Design Tasks taskpane and drag the field onto the form).

That should do the trick.

 Wow!  I have been trying to find a solution for two days now, thank you, thank you, thank you....

Toril