Depending on what exactly the options are and their corresponding values, there are a few ways you can accomplish this.

Generally a Vlookup() formula would be the way to go. Have a look at Vlookup in Excel help.

If the value is a multiple or other pattern of the option, you may be able to use a simple arithmetic formula to get the result.

If you are still having trouble, post back a sampling of the options vs. the results and we can help.