I can't guarantee anything of course - it's different for every person. Out students' median score on the official test (post taking the course with us), is between a 700 and a 710. I don't know companywide how students score on pre-course practice tests, but speaking anecdotally about my own courses, most students start the course between about 550 and 650.

So I'd say you're in a good position - but again no guarantees. A 720 is, by definition, really hard to get!

(Also, FYI - you listed the number incorrect, but that's not actually very important to your score. The much more important factor is the difficulty level of the questions that you answer. Don't expect the # incorrect to change all that much, even as your score goes up.)