Hi Pmista,
I’m glad you reached out, and I’m happy to help. To reiterate, your GMAT score is based on not only the number of questions you answer correct/incorrect, but also the difficulty of those questions, among other things. So, when you scored Q48, you likely got a few lower level questions wrong. In any case, Q48 and Q49 are some great practice test scores, so nice work! Also, if you want any advice on how to improve your GMAT quant skills, feel free to reach out.
Good luck!