There are 124 story books in the library, 56 of which were lent out today, and 28 were returned. How many story books are there in the library now?
图书室有故事书124本，今天借出56本，还回28本．现在图书室有故事书多少本？
<gadget id="calculator">124 - 56</gadget>
<output>68</output>

<gadget id="calculator">68 + 28</gadget>
<output>96</output>

<result>96</result>