Candice read 3 times as many books as Amanda in their school's Book Tournament. Kara read half the number of books that Amanda read, and Patricia read 7 times the number of books that Kara read. If Candice read 18 books, how many books did Patricia read?
Amanda read 18/3 = <<18/3=6>>6 books.
Kara read 6/2 = <<6/2=3>>3 books.
Patricia read 7 x 3 = <<7*3=21>>21 books.
#### 21