Answer:
there are 45 pages in the book
Explanation:
If Joe has read 40% of the book, then he has 60% of the book left to read. Let's let "x" represent the total number of pages in the book.
If Joe has 18 pages left to read, that means he has already read:
0.6x = x - 18
Solving for x, we get:
0.4x = 18
x = 45
Therefore, there are 45 pages in the book.