There are 20 more science books than story books, and fewer story books than science books (1/3), how many story books are there?
科技书比故事书多20本，故事书比科技书少(1/3)，故事书有多少本．
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">20 / (1/3)</gadget>
<output>60</output>

<gadget id="calculator">60 - 20</gadget>
<output>40</output>

<result>40</result>