[Orgmode] decimal fractions when summing up large numbers

[Rainer Thiel]

I have a problem I am confident there is a solution to.  I even
suspect it may be explained in the manual, but can't for the life of
me find it:

Summing up small numbers in tables isn't a problem even when they have
digits after the decimal point.  For example, org-table-sum applied on
the table

| 10000.7 |
| 10000.5 |
| 10000.3 |

correctly gives 30001.5.  On the other hand, applied on the table

| 100000.7 |
| 100000.5 |
| 100000.3 |

org-table-sum gives 300002, the correctly rounded value of 300001.5,
which would be the exact value.

How can I make org-table-sum deliver the exact value?

If this is explained in the manual, please point me to the relevant section.

Many thanks in advance

Rainer
-- 
Prof. Dr. Rainer Thiel
Institut für Altertumswissenschaften
07737 Jena, Germany (EU)
address@hidden