Problem: Scale text changes value when exporting or printing
The scale text is correct when viewing the layout in ArcMap, but it changes when printing or exporting the map.
This happens if the scale text element is not visible within the extent of the map window when the map is printed or exported.
Solution or Workaround
Make sure the Scale Text element is visible in the map window when exporting or printing: zoom to the full extent of the layout prior to exporting or printing.