GMAT Strategy

hello all! I am looking to get a 550 on the GMAT in two weeks. I have been studying all summer and my practice tests results are as follows
MGMAT CAT: 520 (33 Q 28 V) no essay or IR
GMAT Prep 1: 510 (35 Q 25 V) no essay or IR
GMAT Prep 3: 480 (35 Q 21 V)--) I took this test under real test conditions in a library with essay and IR, I had to leave half way through test and finish at home due to there being screaming children and someone who would not stop talking to me. I think these things combined are why my score dropped.
I reset my GMAT prep tests yesterday and took one and got a 550 (35 V 30 Q) note: I did take essay and IR on these (8 on IR)

My question... Is that pretty accurate? I did see a few quant questions that were repeats but I had taken my first prep test so long ago I did not remember any of the answers so it didn't mess with my timing. I am happy to finally have reached my goal and will take another practice test this weekend to see if I can get that score again. But I was just confused, when I got the 510 on Gmat prep 1 I missed 17 quant and received the 35... I missed 20 on the test yesterday and still received the 35? I just thought that was a little strange. Thanks for the advice!

My question... Is that pretty accurate? I did see a few quant questions that were repeats but I had taken my first prep test so long ago I did not remember any of the answers so it didn't mess with my timing. I am happy to finally have reached my goal and will take another practice test this weekend to see if I can get that score again. But I was just confused, when I got the 510 on Gmat prep 1 I missed 17 quant and received the 35... I missed 20 on the test yesterday and still received the 35? I just thought that was a little strange. Thanks for the advice!

There is the potential for your score to be inflated a bit with a retake. Even when you don't remember the answers, seeing familiar questions is strangely comforting, so the psychological experience is a bit different than it would be with 100% fresh material. That said, I've seen plenty of students do the retake, then take the official test a few days later, and end up with scores that are basically identical. So treat it as a good sign, but take the result with a grain of salt. Your next practice exam will shed some more light on where you currently stand.

And last, the number of questions you answer correctly is only part of the equation - the algorithm is also taking into account the difficulty level of the questions you miss, so it's possible to miss an identical number of questions on two successive tests and have scores that are substantially different.

You will drive yourself crazy looking at the number right and wrong and trying to get an accurate indication of score. Almost everyone who takes the exam gets between 50-70% correct. It is about the difficulty of the questions you get correct, not the count. So, in short, this does not seem abnormal.