Thank you that was very helpful and informative. But from the Help it didn't
look as though I can do all 3 functions that I need. Am I mistaken?
=ROUND(SUM(T3/21.7),3)
this formula just calculates to the third decimal. It doesn't Round up when
the last digit is 5 or greater or Round down when the last number is 4 or
less, right?
Thanks again you are always so very helpful!

~Roxy

Let's rephrase something:
Excel ALWAYS calculates to its maximum decimals, which is 15, I think.
ROUND simply cuts it off at whichever point you want, so you want
"=ROUND(SUM(T3/21.7),2)" (Teethless mama's formula). Or possibly use
Martin's, but only if that is really what you want. He gave you
technically what you asked for, but it could give false answers with 2
roundings: For instance 1.2445 ought to be rounded to 1.24 when
showing two places, but if you round first to three places, then to
two you get 1.25. I can't think of a good reason for that to be
correct.

Rounding 5 up and 4 down is the standard in the world, or at least
country, so Excel's basic ROUND function does just that. If you wanted
to do a different form of rounding, THAT would be more complicated.

Another option would be to use =ROUND(SUM(T3/21.7),3) and then format
the cell to 2 decimal places. Just using a specific decimal format
will also show you a rounded (5up, 4down) number. This would give you
the full 3 decimal places, but only show 2 of them (but still have the
potential double-rounding problem I mentioned above). So any further
calculation you do with this number would use the 3 decimals to
calculate.