Katie has read 32% of a book. if she has read 80 pages, how many more pages does katie have left to read

X=total number of pages.
1)we calculate the total number of pages.
32% of x =80
(32/100)x=80
x=(80*100)/32
x=250.

2) we calculate the number of pages don´t read.
number of pages don´t read=250-80=170 

170 pages. 

The answer to your question is b