Thanks everyone for your responses... let me clarify a few things. I was
wrong in listing my cells. They should be:

If A1 = "red" and if B1 = "blue" enter 10 in C1, or
If A1 = "green" and if B1 = "orange" enter 20 in C1, or
If A1 = "purple" and if B1 = "yellow" enter 30 in C1.

If no conditions apply, C1 can be left blank.

You are correct that the data given here is not the real data... just
placeholders. Don't know if the actual data will help, but here's a
description:

In a reference shet, I have two columns and 5 rows, with 5 combinations of
computer types - a database server in the first column, and an application
server in the 2nd column. I need to assign pricing to these combinations.
The selections the user will enter will always be in the pairs as they are
listed in the columns/rows (row1 column1 and row 1 column 2 will always be
paired, row 2 and column 1 and row 2 and column 2 will always be paried, etc).

I am using these lists of hardware in other places, so I need to keep them
in 2 columns - not combine the selections in one cell.

When a combination is picked (by using names and data validation), I need to
insert a price in the open cell (C1).

I'm going to try some of the options above and see if they work.

Thanks!