Question 93
Andriy read a big book for a month. He was reading the book according to a schedule: from 1 until 20 April he read in average 20 pages per day, from 6 until 25 April he read in average of 30 pages per day, and from 11 until 30 April he read in average of 40 pages per day. What are maximum and minimum amounts of pages, that this book could contain?