You cannot be sure.
The way the test works is if you answered one question right, the next question will be a little bit harder. If you answered it wrong, the next question will be a little bit easier. It will keep doing this pattern until it's very sure about your placement (so the number of questions a person has to answer can vary before the test determines this). It's also broken up in categories so you have to do well on all of them; you cannot be weak in one.
So if we go by extremes, you can:
- You can answer few questions (like 70), answered them all correctly, and passed with flying colors.
- You can answer few questions (like 70), and bombed the test, and you failed miserably.
- You can answer a lot of questions (like 130), and you answered a lot of right ones, but you answered a couple of wrong ones too, and passed slightly above what's expected for you to be an EMT.
- You can answer a lot of questions (like 130), and you answered a lot of right ones, but you answered a couple of wrong ones too, but not enough to pass slightly above what is expected to be an EMT.
And that's overall. If you start thinking about categories, you could've answered a couple of questions about operations, totally bombed it, answered flawlessly on everything else, and failed because of the operations category. So you could've answered like 75 questions, did really well on everything else, but you failed one category, and failed the test because of it. See?
I also think their are questions that don't count towards anything, and they are just there? I forget.
So all you can really get from the numbers is not whether you passed or failed, but how close you were to what is expected to pass as an EMT if you passed or failed.