Can you provide a little more information about your problem? Where are these acreages being stored and retrieved from? What is it you are trying to do that you need to change the precision of that number to 2 digits right of the decimal? The context of this problem helps me to to understand what sort of advice to give you.
Yes, I have stored my aguse information in a geodatabase. I have added a field in which I would like to calculate total acreage in a section and provide a report with the total acreage of a certain land use feature. Once I have added a new field and calculated the acreage, the number has 12 or 13 numbers after the decimal. For example, acreage = 123.236545231236. Here, I would like to use the Calculate Geometry tool to perform a "trim" of the number where all the attributes will be trimmed to two decimal places.
Is this enough? Sorry if this is a little confusing. Thanks for your help!