Please try the steps below to change the scale ratio.
Choose View > Tools > Analyze to open the Analyze panel.
Click on the Measuring tool, and then pick one of the Measurement types: Distance, Area or Perimeter.
Hover over the page and right click (Mac OS: Control+click) and chose Change Scale Ratio from the context menu.
Right click | Change Measurement Scale
Enter the preferred scale ratio in the dialog box:
Enter your preferred measurement scale
When you pick OK, you will see the updated scale ratio, as long as you still have the Measuring tool selected in the Analyze panel:
The updated scale ratio is visible when you have the Measuring tool selected
Hi. I Choose View > Tools > but there is no" Analyze" tab
Look under Edit - Analysis...
Where is it now? there is no Analysis under the Edit menu.
Right-clicking on a drawing with the Measuring Tool selected no longer seems to have the option to Change Scale Ratio. Is that set somewhere else now?
Adobe Acrobat Pro DC v2018 for Mac
I am having the same issue its not there anymore