There is, although it’s not a feature directly built into either app. This is possible through the power of AppleScript (don’t worry, I’m not going to ask that you learn AppleScript in order to carry out this job). Instead, I’ll direct you to the Mac OS X Automation site. Here you’ll find an AppleScript and Pages page that provides instructions for using the free Pages Data Merge utility (the page also includes a link to that utility). As its name suggests it lets you incorporate data found in a Numbers spreadsheet into a Pages documents.