There are 42 story books, and there are fewer science books (1/3) than story books. How many science books are there?
故事书42本，科技书比故事书少(1/3)，科技书多少本？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">42 * (2/3)</gadget>
<output>28</output>

<result>28</result>