Question

there are 60 students in advanced math classes 57 students got passing grades what percent of the students passed

Answer 1

57 / 60 will give you the percentage! :) 

95% of students passes.

Answer 2

To get the percent of students who passed, you put 57 over 60 because out of 60 students, 57 of them passed...  Then you divide 57 by 60. 
So 57/60 = 0.95
Move the decimal point two places to the right to convert the decimal to a percent and your answer is 95%

Hope this helps :)