Final answer:
Alex needs to know the number of pages in each book and the total number of pages in all 6 books to calculate how many pages to read each month for the summer reading program.
Step-by-step explanation:
To determine how many pages Alex needs to read each month for the summer reading program, Alex needs to know the number of pages in each book and the total number of pages in the 6 books. Knowing the total number of pages will help him divide that amount by three (the number of months) to find out how many pages he needs to read each month. The total number of days and the number of weeks in June, July, and August are not necessary for this calculation as the time frame (3 months) has already been determined.