Difficulty+Medium+Basic = 100...①
60×3- (middle +3 radix)+radix = 100
180- intermediate -2 radix = 100
Middle +2 group = 80...②
① ② Subtraction can get:
Difficulty-foundation = 100-80=20 questions
That is, there are 20 more questions than the basic questions.
So the answer is: a lot, 20.