Hi Sunaina7,
In general, Schools will NOT take the best 'pieces' of the Scores that you submit, but individual Programs might have a different mindset about doing so (meaning that you might think about contacting them directly and asking). While a 660 is a strong overall Score, you would likely be better off submitting the 660/Q48 - since many Business Schools view an Applicant's Quant Scaled Score as an indicator of how that Applicant might handle the 'academic side' of the Program - and a Q48 would be much better for you (as a Q40 would be seen as a 'red flag' at certain Programs).
Depending on the Schools that you plan to apply to, you would likely find it beneficial to speak with an Admissions Expert about your overall profile and plans. There's a Forum full of those Experts here:
https://gmatclub.com/forum/ask-admissio ... tants-124/GMAT assassins aren't born, they're made,
Rich