Can you explain how to solve this math problem: Jesse is desperately trying to finish a book for a school book report due on Monday so he can play this weekend. Friday afternoon, he read the first 5 chapters, which were 10, 15, 27, 12, and 19 pages, respectively, before taking a break. To his dismay, he found that he was only 1/3 of the way through the book. How many pages does he still have to read?