Explanation
to get the fraction of Nonstudents that disaproved
[tex]\text{fraction}=\frac{total\text{ nonstudents that disaproved}}{\text{total nonstudents}}[/tex]then
let
total nonstudents that disaproved=353
total nostudents=85+353+47=485
now, replace
[tex]\text{fraction}=\frac{353}{485}\rightarrow k[/tex]so,the answer is k