There are 180 popular science books in the school library, 68 books are lent out in the morning, and 25 books are returned in the afternoon. How many popular science books are there in the school library now?
学校图书室有科普图书180本，上午借出68本，下午还回25本．现在学校图书室有科普图书多少本？
<gadget id="calculator">180 - 68</gadget>
<output>112</output>

<gadget id="calculator">112 + 25</gadget>
<output>137</output>

<result>137</result>