Obviously read a 200-page book, but read 25% of the whole book in 5 days. According to this calculation, how many days can I read the entire book? How many.
明明看一本200页的书，5天看了全书的25%．照这样计算，几天能看完全书？多少．
<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/4) / 5</gadget>
<output>1/20 = around 0.05</output>

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

<result>20</result>