Coral is reading a book that is 600 pages long.  She reads half of it in the first week, and 30 percent of the remaining pages the second week. How many pages must she read the third week in order to finish the book?
How many pages does Coral read in the first week? ** Week 1:600/2=300
How many pages does Coral have left to read after the first week? ** 600-300=<<600-300=300>>300 pages remain
How many pages does Coral read in the second week? ** Week 2:300(.30)=90 pages
How many pages does Coral have left to read after the second week? ** 300-90=<<300-90=210>>210 pages remain
How many pages must she read the third week in order to finish the book? ** Week 3:210 pages
#### 210