- 1). Click "Start," type "Calculator" into the search and then click the application link.
- 2). Click "Start," click "Control Panel," then "System and Security" and then "Administrative Tools." Double-click "Computer Management" and enter your password. Hit "Enter."
- 3). Click "Disk Management." On the right, your hard drives will appear. Add the volume space together in calculator. In the following example, assume one partition is 400 gigabytes (GB) in size and the other is 100 GB in size.
- 4). Divide the smaller sized partition by the larger-sized number, in our example this results in 0.25. Divide 1 by the resulting number from the first division, so 1 divided by 0.25 is 4. The partition ratio is 1:4.