It is so hard to say....everyone learns differently.
If you've done any sports before, that will help you.
If you've done sports that required a lot of balance & coordination (gymnastics, dance, yoga, karate, etc), that will help you more.
If you've done much roller skating/blading, or downhill skiing, that will help you a LOT.
And it will depend on your ability to pick up new physical movements, how unafraid you are, AND how much you practice on your own.
If you have crappy rental skates, vs a decent pair of your own skates, that also can make a big difference.
Go in to have fun, work hard, and it remains to be seen the rate you progress at. Enjoy!