At the bookstore, Sarah bought 6 paperback books and 4 hardback books. Her brother bought one-third as many paperback books as Sarah bought, and two times the number of hardback books that she bought. How many books did her brother buy in total?
Thoughts? Step-by-step reasoning:
Her brother bought 6 / 3 = 2 paperbacks. He bought 4 * 2 = 8 hardbacks. In total he bought 2 + 8 = 10 books.
Thus, the answer is 10.