1-(40%+35%+23.5%)

= 1-98.5%,

= 1.5%,

Class size: 3÷ 1.5%=200 people,

The number of outstanding students is: 200×40%=80 (people),

The number of people with good grades is: 200×35%=70 (people).

The qualified number is: 200×23.5%=47 (persons),

Fill in the form as follows: the total number of people who passed the exam is 80 70 47 3 200 (2)40%-35%=5%,

(3) Suggestion: You can learn from students with good grades and ask more questions.

So the answer is: (1) 80,70,47,200; (2)5; (3) You can learn from students with good grades and ask more questions.