To save a PowerPoint presentation as PDF and have multiple PowerPoint slides on a single PDF page follow these steps:
1. Open a PPTX file in PowerPoint.
2. Go to the File menu and click on the Save As option.
3. In the dialog window, from the “Save as type” drop-down menu, choose PDF and click on the Options… button.
4. In the Options dialog window, look for a “Publish what” drop-down menu and select Handouts.
5. Next, choose the number of Slides per page on the right.
6. Click OK.