In the "Book Corner" of the class, add 113 popular science books and divide by 2, which is equal to the number of literature and art books. There are 68 literature and art books. How many general science books are there in the "Book Corner"? (solution by equation)
班级"图书角"里科普书的本书加上113本，再除以2，就等于文艺书的本数，文艺书有68本，"图书角"有多少本科普书？(用方程解)
<gadget id="calculator">113 / 2</gadget>
<output>113/2 = around 56.5</output>

<gadget id="calculator">68 - (113/2)</gadget>
<output>23/2 = around 11.5</output>

<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(23/2) / (1/2)</gadget>
<output>23</output>

<result>23</result>