Your placements in NITIE Mumbai won’t be much affected if you have below 70% in 12th. Most recruiting companies usually consider MBA performance and graduation scores. If you maintain a good academic record during your MBA, you will have decent offers during NITIE placements. If you have industry-relevant skills and knowledge, your 12th score will not be a major obstacle during placements.
Generally, placements do not get affected by your class 12th marks. But there are some cases where it may be considered. This mainly depends on the interviewer or the company.
So, it can never be known exactly what the interviewers want in their potential candidates. So try to work hard and make your profile stand out among others. Even if you have scored less in your class 12th, try improving your performance ahead. This will show your hard work and improvement which is also an important factor for being shortlisted during placements.