Stacy:

This was a bit tougher than I thought but this formula does the
trick....

=SUM(ROUNDDOWN(_100ths,0))+ROUND(SUM(_100ths,-SUM(ROUNDDOWN(_100ths,0)))*0.6,2)

I like to use Named Ranges in Big Formulas, they make more sense.
If you simply enter "A1" wherever you see "_100ths" then this will
solve your quandry...Mark