You specify how you want dimensions to appear by default for your current Inventor document.
Similarly, you specify default tolerance behavior on a per-document basis.
You specify dimension and tolerance default options in the Document Settings dialog box, but you can also access them in the Dimension Properties dialog box.
Click Tools tab
Options panel
Document Settings
.
In the Units tab of the Document Settings dialog box, under Modeling Dimension Display, choose the degree of precision you want to apply to dimensions:
Also under Modeling Dimension Display, choose how you want dimensions to appear in sketches:
Display as Value. Shows the nominal dimension.

Display as Name. Shows the dimension as a parameter name.

Display as Expression. Shows the dimension as an expression.

Display Tolerance. Shows the tolerance for the dimension.

Display Precise Value. Shows the dimension value, ignoring any precision setting.

Click Apply to apply the settings and continue working in the Document Settings dialog box, or click OK to finish and exit the command.
Click Tools tab
Options panel
Document Settings
.
In the Default Tolerance tab of the Document Settings dialog box, choose either or both of the following:
Click Apply to apply the settings and continue working in the Document Settings dialog box, or click OK to finish and exit the command.
All dimensions in the current part document that do not have a tolerance applied update with the changed values.