Rachel was organizing her book case making sure each of the shelves had exactly 9 books on it. If she had 6 shelves of mystery books and 2 shelves of picture books, how many books did she have total?
<gadget id="calculator">6 + 2</gadget>
<output>8</output>

<gadget id="calculator">9 * 8</gadget>
<output>72</output>

<result>72</result>