It's a trick, but it might be useful if you don't want to pay a subscription just to make one twiddle in a one Word document. As of today – 28 March 2014 – Microsoft Office for iPhone is completely free. Not just free as in you can read a document but must pay to edit or create ones, it's completely free.
But you can run iPhone apps on your iPad. They don't look great. This one doesn't look as good as the proper iPad version of Office released yesterday. But it is Office and it will open Word and Excel documents. Possibly also PowerPoint but, seriously.
You do still have to sign up for a Microsoft account and there are myriad better ways to write and edit documents than on the scaled-up iPhone Office but it works.