Solution 1:

The simplest way is at a command line do: systeminfo

You will get a section that looks like:
Total Physical Memory: 16,383 MB
Available Physical Memory: 926 MB
Page File: Max Size: 19,868 MB
Page File: Available: 4,562 MB
Page File: In Use: 15,306 MB


That is taken directly from one of my machines. That info is near the top.