Among the extracurricular readings in the school library, it is known that "Children's Comics" (1/2) and "Children's Stories" (1/4) are 24; "Children's Comics" (1/6) and "Children's Stories" (1/4) is 20 books. How many copies of "Children's Stories" are there?
学校图书室的课外读物中，已知《儿童漫画》的(1/2)与《少儿故事》的(1/4)是24本；《儿童漫画》的(1/6)与《少儿故事》的(1/4)是20本．《少儿故事》有多少本？
<gadget id="calculator">24 - 20</gadget>
<output>4</output>

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

<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/2) - (1/6)</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">4 / (1/3)</gadget>
<output>12</output>

<gadget id="calculator">12 * (1/2)</gadget>
<output>6</output>

<gadget id="calculator">24 - 6</gadget>
<output>18</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">18 / (1/4)</gadget>
<output>72</output>

<result>72</result>