Just about any beginner can average about 10mph. That would include stops about once every hour. So 15 or so hours is reasonable. If you are not used to it though, I wouldn't try to do more than 50 or 60 miles a day and by halfway through the second day you might start to get sore in places you didn't know you had places. You don't say if you are taking any gear. When I say sore, I also mean your feet, so make sure you have good biking shoes. What about repairs if you have a flat or other problems? There are a lot of things to consider if you have never done something like this before. Good luck. Email me if you have more questions.
