Formula to look through data in multiple columns and return corresponding results contained in a different column?

[ScubaPeeve]

Hello,

I was hoping that someone might be able to help me with a formula that I am looking to create to find a particular piece of data that may be contained in one of three columns and return a figure that is contained in a different column. The sample spreadsheet is as follows:

Column 1 Column 2 Column 3 Column 4 Column 5
T01 T04 T07 1 2
T02 T05 T08 3 4
T03 T06 T09 5 6


Looking to return the value in Column 4 based on a specific value that may be in either Column 1, Column 2, or Column 3.

Example:

for one row I would be looking for the corresponding number in Column 4 that is associated with T02 in Column 1. For the next row I would be looking for the corresponding number in Column 4 that is associated with T06 in Column 2. The catch is that the data in Column 1, Column 2, and Column 3 could move around but I am still looking for the corresponding number in Column 4 (i.e. - T02 could move to Column 2 and T06 could move to Column 2). Wanted to be able to write one formula that would be able to look across the first three columns, find the desired data point, and pull back the corresponding number in column 4.

Hope that makes sense. Thank you in advance for any assistance that may be provided.