After reading 100 pages of a book, there are still 15 pages left to read. (1) what percentage of the total number of unread pages? (2) What percentage of the total number of pages read? (3) What percentage of the students have not read? (4) How many more pages have you read than the rest?

After reading 100 pages of a book, there are still 15 pages left to read. (1) what percentage of the total number of unread pages? (2) What percentage of the total number of pages read? (3) What percentage of the students have not read? (4) How many more pages have you read than the rest?

(1) (2) 100 + 15 = 115 (pages) 100 ／ 115 ≈ 87% a: the number of pages read accounts for 87% of the whole book; (3) 15 ／ 115 ≈ 13% a: there are still 13% unread. (4) (100-15) ／ 15 = 85 ／ 15 ≈ 566.7% a: the number of pages read is 566.7% more than the rest