Numbers.app
Where is "Page Setup" in Numbers.app?
Configuring the page layout in numbers works a bit differently that in other OS X apps. Here's the process.
- In the Numbers File menu, select Show Print View.
- On the right side of the Numbers Toolbar, click on the Inspector icon.
- In the Inspector, select the Page Layout tab at the top, second from left.
- Select the desired orientation, say, landscape mode.
- Note the Content Scale slider just above.
Play with the slider until the dynamically resized spreadsheet appears on the virtual page at the size you want.

