Xiaoqing has 9 storybooks, Xiaoxin has 7 comic books, Xiaoqing exchanges 3 storybooks for Xiaoxin 2 comic books, how many books does Xiaoqing and Xiaoxin have now?
小青有9本故事书，小新有7本连环画，小青用3本故事书换小新2本连环画，现在小青、小新各有几本书？
<gadget id="calculator">9 - 3</gadget>
<output>6</output>

<gadget id="calculator">6 + 2</gadget>
<output>8</output>

<result>8</result>