This statement:

They need to be exact because they're being used for look-up values.

and this one:

I should have mentioned it's a lookup value in a database table.

suggest to me that there's some sort of cognitive mismatch between what your code plus database are supposed to accomplish, and what you are actually trying to implement. If the various observations here about the inherent inexactness of floating point values don't solve your database lookup problem, you may need to start another thread about what the real problem is (trying to do database lookups on the basis of computed values or something like that).