Not surprising that the top 5 students of a course may only have a GPA of 3.77. Different courses have different difficulty levels, competitiveness and assessment.
For example, courses that are more subjective - e.g. design-based where art is involved or any other subjects where it is more difficult to determine "correct" answers unlike fact-based subjects - you will find that it is pretty much impossible to find perfect scorers. For such courses, the disparity between the 1st position and his runner-up may also be very wide. I know of a gold medallist (1st position) who won MULTIPLE national design awards but his GPA is less than 3.8. The average GPA of his course? only 2 point something.
For other courses where there is a more "fixed" right and wrong answers for examinations - more maths-based courses eg. Engineering, accountancy etc. where you may depend more on hard-core mugging rather than talent to score...
They may have the entire top 10% scoring GPAs of 3.9 to a perfect 4.00. In such cases, the average GPA score for the entire cohort may already very well be above 3.5. With such close GPA scores for the top scorers, how they determine the top 3 positions (who may all very well have perfect 4s) is the number of distinctions they earned throughout their 3 years.
So don't be too impressed if someone tells you he has a GPA of 3.9 and above. That person may very well be at the 49th out of 50 positions in his class.
Likewise, don't look down on the person with 3.7 GPA. He may already be the top scorer, lol.
Hmmm. Then that seems to be the problem with the poly right? I mean. NTU would assume that a 3.8 in mech engin would be the same as a 3.8 from biz or accountancy. If both are applying to a course in ntu that has no diploma pre-requisites, Ntu would view both as equals.