In PowerPoint, just copy and paste the shapes containing the table or chart. Afterwards you can edit the copy. It is also possible just to copy a complete slide, and edit the tables and chart on the copied slide.
In Excel it is not possible to ‘just’ copy and paste a table or chart. When using Ctrl-C while you have selected a whole table, the following window pops up.
To paste the table, use combination Ctrl+Shift+D. The copy can be edited afterwards.
In order to copy a complete sheet and still be able to edit the tables and chart on the copied sheet, you have to use the ‘Copy’ menu item on the OfficeReports ribbon in box ‘Sheet’.