Carcass wrote:
The public library has exactly 2 floors. It has 2/3 as many shelves on its 2nd floor as it does on its 1st. If the second floor has 5/6 as many books per shelf as the first floor, what fraction of the library's books are on the first floor?
A. 1/4
B. 5/14
C. 5/9
D. 9/14
E. 5/6
Let's choose values that satisfy the given information...
The library has 2/3 as many shelves on its 2nd floor as it does on its 1st. So, let's say there are 
3 shelves on the 1st floor, which means there are 
2 shelves on the 2nd floor
The second floor has 5/6 as many books per shelf as the first floorSo, let's say there are 
6 books per shelf on the first floor, which means there are 
5 books per shelf on the second floor.
The total number of books on the first floor = (
3)(
6) = 
18 books 
The total number of books on the second floor = (
2)(
5) = 
10 books 
The TOTAL number of books in the library = 
18 + 
10  = 
28  What fraction of the library's books are on the first floor?Of the library's 
28  books, 
18 are on the first floor. 
Answer: 
18/
28 = 
9/14Answer: D