Nope - this is not the correct solution to the requirement.
The OP question was about _display_ format - not actual data.
With the ROUND() function you cut away precision and any data processing afterwards can only use the precision level provided by the result of the ROUND() function.
Display format and data precision are two separate concepts that mustn't be mixed up.
I tried to explain this in more detail and provide more pointers for follow up in this post: Community criss cross puzzle posting in multiple locales.
- Lars