Answer:
6 shelves
Explanation:
Let the number of shelves needed be s
If the total number of books to be displayed is 390books
If Each shelf can hold 65 books, then;
1 shelf = 65books
To know the total shelf needed;
s = 390 books
Divide both expressions
1/s = 65/390
65s = 390
Divide through by 65
65s/65 = 390/65
s = 390/65
s = 6
Hence 6 shelves will be needed