There are 450 science books in the library, which is 25% less than story books. How many story books are there?
图书馆有科技书450本，比故事书少25%，故事书有多少本？
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 - (1/4)</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">450 / (3/4)</gadget>
<output>600</output>

<result>600</result>