You can probably get a 900 by just showing up and randomly checking boxes. Someone with that low of a score is probably not smart enough to devise a way to cheat, as the SAT is managed very strictly.
So if she studied, took some practice exams - I believe its entirely possible she would be able to get a significantly higher score.
Why are they accusing her of cheating? Do they have some evidence?
Her answers were apparently very similar to someone sitting next to her, which is why she was flagged (by the computer checking the results, I believe). The press always leave that part out.
If they still score it the same way, you get 1 point for every correct answer but get docked 1.25 points for every wrong answer. So it’s best not to guess randomly at an answer, better to leave them blank. (Unless you can eliminate some of the wrong answers, then your odds improve at guessing correctly and improving the overall score).
There is a penalty for guessing incorrectly so random guessing will not increase your score.
The intended mean on any section is 500; the intended standard deviation is 100. (Actual values vary). Minimum score is 200 on each section; the maximum is 800.
Var(X + Y) = Var(X) + Var(Y) + 2Cov(X,Y).
I don’t know if the scores are independent. If so then the intended standard deviation on both sections is sqrt(20000) = 141.
Going from a score of 480 to a score of 700 is going from the zeroth percentile to the 2nd percentile. Even a score of 810 is the 9th percentile.
However going from 900 to 1230 is going from the 24th percentile to the 95th percentile. This is a huge jump.