The school bought 9 packs each of story books and science books. There are 25 story books per pack, and 18 science and technology books per pack. How many books did you buy in total?
学校买来故事书、科技书各9包．故事书每包25本，科技书每包18本．一共买来书多少本？
<gadget id="calculator">25 + 18</gadget>
<output>43</output>

<gadget id="calculator">43 * 9</gadget>
<output>387</output>

<result>387</result>