Answer:
18x + 109 = 555
Explanations:
The total number of pages = 555
The number of pages read last week = 109
The number of hours used for reading the remaining pages = x
The number of pages read in 1 hour = 18
The total number of books he will read in x hours = 18x
Total number of books = (Number of books read last week) + 18x
555 = 109 + 18x
That is, 18x + 109 = 555