GPA is only a small part of the equation.
First, what courses are you taking? APs count more as do the "hard" math, science, English and language courses. A high GPA in low level courses won't count as much as a similar GPA in more difficult subjects/classes.
Second, what is your class rank? If you have a 3.7 but everyone else in your class has a 3.71 or better . . .
Third, how are your test scores? Again, they alone aren't determinative but are factored in with the above.
Fourth, how difficult is your school? Some schools are known for being very strong academically and standing a bit lower in rank at these schools may not hurt you.
As you can see, there is no one answer. You should always strive to take the hardest classes you can manage and do as well as possible in them. That's all you can do -- the rest will take care of itself.